Structure and method for improving adhesion strength of coating

ABSTRACT

A method and a structure for improving adhesion strength of a coating are provided. The method includes: step  1 ), preparing textured patterns, where at least one type of pattern is textured on a surface of a substrate using a laser process based on bionics; step  2 ), regulating a parameter, where a spraying process parameter is regulated based on a parameter of the textured patterns; and step  3 ), spraying a coating, where spraying is performed on the substrate obtained in step  1 ) using a supersonic plasma spraying method.

This application claims priority to Chinese Patent Application No. 201710345260.6, titled “STRUCTURE AND METHOD FOR IMPROVING ADHESION STRENGTH OF COATING”, and filed with the Chinese State Intellectual Property Office on May 16, 2017.

This application claims priority to Chinese Patent Application No. 201710344801.3, titled “STRUCTURE AND METHOD FOR IMPROVING ADHESION STRENGTH OF COATING BY REGULATING DEPTH OF TEXTURED PATTERNS”, and filed with the Chinese State Intellectual Property Office on May 16, 2017.

This application claims priority to Chinese Patent Application No. 201710345254.0, titled “STRUCTURE AND METHOD FOR IMPROVING ADHESION STRENGTH OF COATING BY REGULATING TEXTURING DISTANCE”, and filed with the Chinese State Intellectual Property Office on May 16, 2017.

This application claims priority to Chinese Patent Application No. 201710344775.4, titled “STRUCTURE AND METHOD FOR IMPROVING ADHESION STRENGTH OF PLASMA-SPRAYED COATING BY CHANGING DIAMETER OF TEXTURED RECESS”, and filed with the Chinese State Intellectual Property Office on May 16, 2017.

This application claims priority to Chinese Patent Application No. 201710345262.5, titled “STRUCTURE AND METHOD FOR IMPROVING ADHESION STRENGTH OF NICKEL-BASED COATING USING COMPOSITE TEXTURED PATTERNS”, and filed with the Chinese State Intellectual Property Office on May 16, 2017.

This application claims priority to Chinese Patent Application No. 201710347052.X, titled “STRUCTURE AND METHOD FOR IMPROVING ADHESION STRENGTH OF COATING BASED ON TEXTURED PATTERNS FORMED BY ALTERNATELY COMBINING SYMMETRICAL PATTERNS”, and filed with the Chinese State Intellectual Property Office on May 16, 2017.

This application claims priority to Chinese Patent Application No. 201710345265.9, titled “STRUCTURE AND METHOD FOR IMPROVING ADHESION STRENGTH OF COATING BY CHANGING SIDE LENGTH OF SQUARE TEXTURED PATTERNS”, and filed with the Chinese State Intellectual Property Office on May 16, 2017.

This application claims priority to Chinese Patent Application No. 201710345263.X, titled “STRUCTURE AND METHOD FOR IMPROVING ADHESION STRENGTH OF COATING BASED ON TEXTURED PATTERNS FORMED BY ALTERNATELY COMBINING BIONIC ANIMAL SURFACE PATTERNS AND CIRCLES”, and filed with the Chinese State Intellectual Property Office on May 16, 2017.

This application claims priority to Chinese Patent Application No. 201710345266.3, titled “STRUCTURE AND METHOD FOR IMPROVING ADHESION STRENGTH OF COATING BASED ON SIDE LENGTH OF HEXAGONAL TEXTURED PATTERN ON SURFACE OF TURTLE SHELL”, and filed with the Chinese State Intellectual Property Office on May 16, 2017.

This application claims priority to Chinese Patent Application No. 201710344773.5, titled “STRUCTURE AND METHOD FOR IMPROVING ADHESION STRENGTH OF COATING BASED ON TEXTURED PATTERNS FORMED BY ALTERNATE COMBINATION”, and filed with the Chinese State Intellectual Property Office on May 16, 2017.

This application claims priority to Chinese Patent Application No. 201710347053.4, titled “STRUCTURE AND METHOD FOR IMPROVING ADHESION STRENGTH OF COATING BASED ON TEXTURED PATTERNS FORMED BY ALTERNATELY COMBINING SQUARES AND CHANNEL SHAPES”, and filed with the Chinese State Intellectual Property Office on May 16, 2017.

This application claims priority to Chinese Patent Application No. 201710344817.4 titled “STRUCTURE AND METHOD FOR IMPROVING ADHESION STRENGTH OF SUPERSONIC PLASMA-SPRAYED COATING BY CHANGING TEXTURING PARAMETER OF CHANNEL SHAPE”, and filed with the Chinese State Intellectual Property Office on May 16, 2017.

This application claims priority to Chinese Patent Application No. 201710344821.0, titled “STRUCTURE AND METHOD FOR IMPROVING ADHESION STRENGTH OF WEAR-RESISTANT ANTI-FATIGUE COATING BASED ON COMBINATION-SHAPED TEXTURED PATTERNS”, and filed with the Chinese State Intellectual Property Office on May 16, 2017.

This application claims priority to Chinese Patent Application No. 201710344824.4, titled “STRUCTURE AND METHOD FOR IMPROVING ADHESION STRENGTH OF WEAR-RESISTANT ANTI-FATIGUE COATING BY CHANGING TEXTURING PARAMETER OF CHANNEL SHAPE”, and filed with the Chinese State Intellectual Property Office on May 16, 2017.

The above Chinese Patent Applications are incorporated herein by reference in their entireties.

FIELD

The present disclosure relates to the technical filed of coating material, and particularly to a structure and a method for improving adhesion strength of a coating.

BACKGROUND

A plasma-sprayed coating can be used in processing of large-size parts, and can have a large thickness, and thus the plasma-sprayed coating is widely applied in the engineering field. However, the plasma-sprayed coating is bonded with a substrate mechanically, which results in a low bonding force of the sprayed coating. Adhesion strength between the substrate and the coating is a critical factor affecting service performance of a thermal-sprayed coating. In a case that the sprayed coating has low adhesion strength, a failure may occur at an interface of the coating in service. Therefore, multiple means such as peening and chemical degreasing are used before the spraying. During the chemical degreasing process, a chemical reaction occurs on a surface, and a new oxide is produced, which results in a change in a chemical composition on the surface of the substrate. Also, the used chemicals are harmful to humans and the environment. The surface of the substrate is roughened to some extent during the peening process, but obtained patterns are irregular and are not easily controlled. Also, a sandblasting process may result in deformation of the substrate, and may even result in micro-cracks on the surface of the substrate. It can be seen that the conventional roughening processing before spraying cannot effectively improve the bonding force of the coating.

Therefore, an urgent problem to be solved by those skilled in the art is how to process before spraying to improve a bonding force between the coating and the substrate, so that the sprayed coating can be applied into the engineering practices with a long service life.

SUMMARY

In view of this, a method for improving adhesion strength of a coating is provided in the present disclosure, which, as a processing before spraying, can improve a bonding force between the coating and a substrate, so that the sprayed coating can be applied into the engineering practices with a long service life.

A structure for improving adhesion strength of a coating is further provided in the present disclosure.

In order to realize the above objectives, the following technical solutions are provided in the present disclosure.

The method for improving adhesion strength of the coating includes: step 1), preparing textured patterns, where at least one type of pattern is textured on a surface of a substrate using a laser process based on bionics; step 2), regulating a parameter, where a spraying process parameter is regulated based on a parameter of the textured patterns formed in step 1); and step 3), spraying a coating, where spraying is performed on the substrate obtained in step 1) using a supersonic plasma spraying method.

According to an embodiment, in the method for improving adhesion strength of the coating described above, the parameter of the textured patterns includes one or more of a pattern shape, a pattern distance, a pattern dimension and pattern arrangement.

According to an embodiment, in the method for improving adhesion strength of the coating described above, the pattern shape includes one of a channel shape, a square, a regular hexagon and a circle, or a combination thereof.

According to an embodiment, in the method for improving adhesion strength of the coating described above, the pattern dimension includes one of a depth, a side length, a width and a diameter, or a combination thereof.

According to an embodiment, in the method for improving adhesion strength of the coating described above, the pattern shape includes the channel shape and the circle, and the channel shape and the circle are combined alternately. At least three columns of circular patterns are textured. A preset distance is reserved between each pair of adjacent columns of circular patterns, and the preset distance is greater than a width of a channel-shaped pattern to be textured. A column of channel-shaped patterns are textured between each pair of adjacent columns of circular patterns

According to an embodiment, in the method for improving adhesion strength of the coating described above, the pattern shape includes the square and the circle, and the square and the circle are combined alternately. At least three columns of circular patterns are textured. A preset distance is reserved between each pair of adjacent columns of circular patterns, and the preset distance is greater than a side length of a square pattern to be textured. A column of square patterns are textured between each pair of adjacent columns of circular patterns.

According to an embodiment, in the method for improving adhesion strength of the coating described above, the pattern shape includes the regular hexagon and the circle, and the regular hexagon and the circle are combined alternately. At least three columns of circular patterns are textured. A preset distance is reserved between each pair of adjacent columns of circular patterns, and the preset distance is greater than a length of the longest diagonal line of a regular-hexagonal pattern to be textured. A column of regular-hexagonal patterns are textured between each pair of adjacent columns of circular patterns.

According to an embodiment, in the method for improving adhesion strength of the coating described above, the pattern shape includes a square and a circle, and the square and the circle are arranged alternately. At least three columns of circular patterns are textured. A preset distance is reserved between each pair of adjacent columns of circular patterns, and the preset distance is greater than a side length of a square pattern to be textured. A column of square patterns are textured between each pair of adjacent columns of circular patterns.

According to an embodiment, in the method for improving adhesion strength of the coating described above, the pattern shape includes the square and the channel shape, and the square and the channel shape are combined alternately. At least three columns of channel-shaped patterns are textured. A preset distance is reserved between each pair of adjacent columns of channel-shaped patterns, and the preset distance is greater than a side length of a square pattern to be textured. A column of square patterns is textured between each pair of adjacent columns of channel-shaped patterns.

According to an embodiment, in the method for improving adhesion strength of the coating described above, the pattern shape includes the regular hexagon and the channel shape, and the regular hexagon and the channel shape are combined alternately. At least three columns of channel-shaped patterns are textured. A preset distance is reserved between each pair of adjacent columns of channel-shaped patterns, and the preset distance is greater than a length of the longest diagonal line of a regular-hexagonal pattern to be textured. A column of regular-hexagonal patterns is textured between each pair of adjacent columns of channel-shaped patterns.

According to an embodiment, before step 1), the method for improving adhesion strength of the coating described above further includes a substrate preprocessing step of polishing and cleaning the surface of the substrate.

According to an embodiment, in the method for improving adhesion strength of coating described above, in step 1), the substrate is made of stainless steel.

According to an embodiment, in the method for improving adhesion strength of coating described above, the coating in step 3) is a NiCrBSi ceramic coating. A sprayed coating obtained by the supersonic plasma spraying method has a thickness of approximately 500 μm. A particle size of NiCrBSi powder ranges from 50 μm to 60 μm.

According to an embodiment, in the method for improving adhesion strength of coating described above, the textured patterns prepared in step 1) have a depth ranging from 30 μm to 120 μm, and a diameter ranging from 35 μm to 65 μm.

A structure for improving adhesion strength of a coating is further provided in the present disclosure, which includes a substrate, textured patterns having at least one type of pattern prepared on the substrate, and a coating sprayed on the textured patterns.

According to an embodiment, in the above structure, the textured patterns are in a shape of one of a square, a channel shape, a circle and a regular hexagon, or a combination thereof.

According to an embodiment, in the above structure, the substrate is made of stainless steel, and the coating is a NiCrBSi ceramic coating.

As compared with the conventional technology, the present disclosure has the following advantageous effects.

In the method provided in the present disclosure, a laser texturing method is used for controlling a parameter of a laser process, to obtain textured geometrical patterns with dimensions arranged regularly at a density on the surface of the substrate. The method, as a processing before spraying, can improve a bonding force between the coating and the substrate, so that the sprayed coating can be applied into the engineering practices with a long service life. Also, a spraying process parameter is regulated based on the parameter of the textured pattern, the adhesion strength of the sprayed coating changes with the parameter of the textured patterns and the spraying process parameter, thereby optimizing the parameter of the textured patterns.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the technical solution in the embodiments of the present disclosure or in the conventional technology, in the following, drawings required in the description of the embodiments or the conventional technology will be introduced simply. Apparently, the drawings in the following description show only some embodiments of the present disclosure. For those skilled in the art, other drawings can also be obtained according to the provided drawings without any creative work.

FIG. 1-1 is a schematic diagram showing form of the channel-shaped textured patterns according to a first embodiment of the present disclosure;

FIG. 1-2 is a schematic diagram showing adhesion strength of channel-shaped textured patterns according to the first embodiment of the present disclosure;

FIG. 2-1 is a schematic diagram showing form of square textured patterns according to a second embodiment of the present disclosure;

FIG. 2-2 is a schematic diagram showing adhesion strength of the square textured patterns according to the second embodiment of the present disclosure;

FIG. 3-1 is a schematic diagram showing form of hexagonal textured patterns according to a third embodiment of the present disclosure;

FIG. 3-2 is a schematic diagram showing adhesion strength of the hexagonal textured patterns according to the third embodiment of the present disclosure;

FIG. 4 shows testing results of an influence of a density of textured patterns on adhesion strength;

FIG. 5-1 to FIG. 5-3 show form of textured patterns with a depth of 35 μm and different diameters according to a fourth embodiment of the present disclosure;

FIG. 6-1 to FIG. 6-3 show form of textured patterns with a depth of 60 μm and different diameters according to a sixth embodiment of the present disclosure;

FIG. 7-1 to FIG. 7-3 show form of textured patterns with a depth of 75 μm and different diameters according to an eighth embodiment of the present disclosure;

FIG. 8 is a curve diagram showing comparison of adhesion strength of a sprayed coating for different textured patterns;

FIG. 9 is a curve diagram of changes of contact area and the adhesion strength of the sprayed coating with an increase in a depth of the textured patterns;

FIG. 10-1 shows formation of a sprayed coating on textured patterns with a distance of 30 μm according to a ninth embodiment of the present disclosure or textured patterns with a diameter of 40 μm according to a tenth embodiment of the present disclosure;

FIG. 10-2 shows deposition of sprayed particles on the textured pattern in FIG. 10-1;

FIG. 11-1 shows formation of a sprayed coating on textured patterns with a distance of 50 μm according to the ninth embodiment of the present disclosure or textured patterns with a diameter of 60 μm according to the tenth embodiment of the present disclosure;

FIG. 11-2 shows deposition of sprayed particles on the textured pattern in FIG. 11-1;

FIG. 12-1 shows formation of a sprayed coating on textured patterns with a distance of 70 μm according to the ninth embodiment of the present disclosure or textured patterns with a diameter of 80 μm according to the tenth embodiment of the present disclosure;

FIG. 12-2 shows deposition of sprayed particles on the textured pattern in FIG. 12-1;

FIG. 13-1 shows formation of a sprayed coating on textured patterns with a distance of 90 μm according to the ninth embodiment of the present disclosure or textured patterns with a diameter of 100 μm according to the tenth embodiment of the present disclosure;

FIG. 13-2 shows deposition of sprayed particles on the textured pattern in FIG. 13-1;

FIG. 14-1 shows formation of a sprayed coating on textured patterns with a distance of 110 μm according to the ninth embodiment of the present disclosure or textured patterns with a diameter of 120 μm according to the tenth embodiment of the present disclosure;

FIG. 14-2 shows deposition of sprayed particles on the textured pattern in FIG. 14-1;

FIG. 15 shows testing results of an influence of a distance on adhesion strength according to the ninth embodiment of the present disclosure;

FIG. 16 shows testing results of an influence of a diameter on adhesion strength according to the tenth embodiment of the present disclosure;

FIG. 17 shows testing results of an influence of a width of a channel-shaped textured pattern on adhesion strength according to an eleventh embodiment of the present disclosure;

FIG. 18 shows testing results of an influence of a length of a channel-shaped textured pattern on adhesion strength according to a twelfth embodiment of the present disclosure;

FIG. 19 shows testing results of an influence of a side length of a square textured pattern on adhesion strength according to a thirteenth embodiment of the present disclosure;

FIG. 20 shows testing results of an influence of a side length of a regular-hexagonal textured pattern on adhesion strength according to a fourteenth embodiment of the present disclosure;

FIG. 21 shows testing results of an influence of a single-shaped pattern and a combination-shaped pattern on adhesion strength according to a fifteenth embodiment of the present disclosure;

FIG. 22 shows testing results of an influence of the combination-shaped patterns with different dimensions on adhesion strength according to the fifteenth embodiment of the present disclosure;

FIG. 23 shows testing results of an influence of a single-shaped pattern and a combination-shaped pattern on adhesion strength according to a sixteenth embodiment of the present disclosure;

FIG. 24 shows testing results of an influence of the combination-shaped patterns with different dimensions on adhesion strength according to the sixteenth embodiment of the present disclosure;

FIG. 25 shows testing results of an influence of a single-shaped pattern and a combination-shaped pattern on adhesion strength according to a seventeenth embodiment of the present disclosure;

FIG. 26 shows testing results of an influence of the combination-shaped pattern with different dimensions on adhesion strength according to the seventeenth embodiment of the present disclosure;

FIG. 27 shows testing results of an influence of a single-shaped pattern and a combination-shaped pattern on adhesion strength according to an eighteenth embodiment of the present disclosure;

FIG. 28 shows testing results of an influence of the combination-shaped patterns with different dimensions on adhesion strength according to the eighteenth embodiment of the present disclosure;

FIG. 29 shows testing results of an influence of a single-shaped pattern and a combination-shaped pattern on adhesion strength according to a nineteenth embodiment of the present disclosure;

FIG. 30 shows testing results of an influence of the combination-shaped patterns with different dimensions on adhesion strength according to the nineteenth embodiment of the present disclosure;

FIG. 31 shows testing results of an influence of a single-shaped pattern and a combination-shaped pattern on adhesion strength according to a twentieth embodiment of the present disclosure; and

FIG. 32 shows testing results of an influence of the combination-shaped patterns with different dimensions on adhesion strength according to the twentieth embodiment of the present disclosure.

DETAILED DESCRIPTION OF THE EMBODIMENTS

The present disclosure aims to provide a method for improving adhesion strength of a coating, which, as a processing before spraying, can improve a bonding force between the coating and a substrate, so that the sprayed coating can be applied into the engineering practices with a long service life.

A structure for improving adhesion strength of a coating is further provided in the present disclosure.

The advantageous effects of the present disclosure are further described below in conjunction with the embodiments. It should be understood that the embodiments are only intended to exemplify the technical solution and are not intended to limit the protection scope of the present disclosure.

A method for improving adhesion strength of a coating is provided according to an embodiment of the present disclosure, which includes step 1) to step 3).

In step 1), textured patterns are prepared. At least one type of pattern is textured on a surface of a substrate using a laser process based on bionics. The substrate is preferably made of a stainless steel, and more preferably is made of FV520B.

In step 2), a parameter is regulated. A spraying process parameter is regulated based on a parameter of the textured patterns formed in step 1).

In step 3), a coating is sprayed. Spraying is performed on the substrate obtained in step 1) using a supersonic plasma spraying method.

The adhesion strength of the coating can be tested. A geometrical form of texture before the coating is sprayed and an SEM form of a cross section of the coating after the coating is sprayed are observed using a scanning electron microscope. A bar-shaped part is adhered onto a surface of the coating using an adhesive paper. A force for peeling the coating off the substrate by pulling the part is measured, to obtain an adhesion force of the coating.

In the method provided in the present disclosure, a laser texturing method is used for controlling a parameter of a laser process, to obtain textured geometrical patterns with dimensions arranged regularly at a density on the surface of the substrate. The method, as a processing before spraying, can improve a bonding force between the coating and the substrate, so that the sprayed coating can be applied into the engineering practices with a long service life. Also, the spraying process parameter is regulated based on the parameter of the textured pattern, the adhesion strength of the sprayed coating changes with the parameter of the textured patterns and the spraying process parameter, thereby optimizing the parameter of the textured pattern.

In the embodiment, the parameter of the textured patterns includes one of a pattern shape, a pattern distance, a pattern dimension and pattern arrangement, or a combination thereof. The spraying process parameter is regulated based on one or more of the pattern shape, the pattern distance, the pattern dimension and the pattern arrangement of the textured patterns formed in step 1). Therefore, the spraying process parameter is optimized, such that optimal adhesion strength between the coating and the substrate can be realized based on the parameter of the textured patterns and the spraying process parameter.

The pattern shape includes one of a channel shape, a square, a regular hexagon and a circle, or a combination thereof. The textured pattern may be in a single pattern shape, and may also be in a shape of a combination of any two or more of the pattern shapes.

Furthermore, the pattern dimension includes one of a depth, a side length, a width and a diameter, or a combination thereof. Different pattern dimensions are taken into account for the patterns in different shapes. For example, the pattern dimension for the square and the regular hexagon includes the side length and the depth. The pattern dimension for the circle includes the depth and the diameter. The pattern dimension for the channel shape includes the width and the depth. In a case that the textured patterns are in a shape of a combination of multiple pattern shapes, the pattern dimensions may be a combination of various dimensions correspondingly.

Furthermore, according to the embodiment, before step 1), the method for improving adhesion strength of the coating further include a substrate preprocessing step including polishing and cleaning the surface of the substrate, to facilitate subsequent processing of the textured patterns and the spraying process, thereby improving a spraying effect.

The spraying process parameter is regulated below with taking different pattern shapes of the textured patterns as a parameter, which is described in the following embodiment in detail.

First Embodiment

A method for improving adhesion strength of a coating is provided in the present embodiment. The pattern shape is a channel shape, as shown in FIG. 1-1. The method includes step S11 to S14.

In step S11, a substrate is preprocessed. A surface of the substrate is polished and cleaned to remove impurities on the surface of the substrate and improve a spraying effect.

In step S12, textured patterns are prepared. Channel-shaped patterns are textured on the surface of the substrate using a laser process based on bionics.

In step S13, a parameter is regulated. A spraying process parameter is regulated based on a complexity degree of the textured patterns formed in step S12, so that the different textured patterns have the same processing depth. For the channel-shaped textured patterns, a laser power is selected to be 14 W, a scanning speed is selected to be 600 mm/s, a frequency is selected to be 20 HZ, and the number of processing is selected to be 2.

In step S14, a coating is sprayed. Spraying is performed on the substrate obtained in step S12 using a supersonic plasma spraying method. A selected spraying device is a high efficient GTV F6 plasma spraying device of the General Research Institute of Mining and Metallurgy. The spraying process parameter includes a spraying voltage of 120V, a spraying current of 440 A, a spraying power of 55 kW, and a spraying distance of 100 mm. Therefore, a coating with a depth is obtained.

The adhesion strength of the coating can be tested. A geometrical form of texture before the coating is sprayed and an SEM form of a cross section of the coating after the coating is sprayed are observed using a scanning electron microscope, and a bar-shaped part is adhered onto a surface of the coating using an adhesive paper, and a force for peeling the coating off the substrate by pulling the part is measured, to obtain an adhesion force of the coating.

Second Embodiment

A method for improving adhesion strength of a coating is provided in the present embodiment. A pattern shape is a square, as shown in FIG. 2-1. The method includes the following steps S22 and S23 in addition to the same steps as the method described above.

In step S22, textured patterns are prepared. Square patterns are textured on the surface of the substrate using a laser process based on bionics.

In step S23, a parameter is regulated. A spraying process parameter is regulated based on a complexity degree of the textured patterns formed in step S22, so that the different textured patterns have the same processing depth. For the square textured patterns, a laser power is selected to be 14 W, a scanning speed is selected to be 600 mm/s, a frequency is selected to be 20 HZ, and the number of processing is selected to be 2.

Third Embodiment

A method for improving adhesion strength of a coating is provided in the present embodiment. A pattern shape is a regular hexagon, as shown in FIG. 3-1. The method includes steps S32 and S33.

In step S32, textured patterns are prepared. Hexagonal patterns are textured on the surface of the substrate using a laser process based on bionics.

In step S33, a parameter is regulated. A spraying process parameter is regulated based on a complexity degree of the textured patterns formed in step S32, so that the different textured patterns have the same processing depth. For the hexagonal textured pattern, a laser power is 12 W, a scanning speed is 4000 mm/s, a frequency is 20 HZ, and the number of processing is 1.

Comparative Example

In order to measure performances of the coating, a geometrical form of texture after the coating is sprayed is observed using a Nova NanoSEM450 model of scanning electron microscope. In order to measure an influence of different textured patterns on an anti-fatigue performance of the sprayed coating, a fatigue performance of the sprayed coating is measured using a rolling-contact fatigue testing machine.

Adhesion strength between the coating and the substrate is tested using a tensile testing machine under conditions of different shapes textured on the surface of the substrate. The tensile testing machine is an MTS809 mode of electronic universal material testing machine. The tensile test is performed after the coating is sprayed on the textured patterns in different shapes prepared in the above embodiments. The adhesion strength is indicated by a ratio of a force under which the coating fractures from the substrate to the area of the coating.

The form of the channel-shaped textured patterns according to the first embodiment is as shown in FIG. 1-1, and adhesion strength of the channel-shaped textured patterns is as shown in FIG. 1-2. The form of the square textured patterns according to the second embodiment is as shown in FIG. 2-1, and adhesion strength of the square textured patterns is as shown in FIG. 2-2. The form of the hexagonal textured pattern according to the third embodiment is as shown in FIG. 3-1, and adhesion strength of the hexagonal textured patterns is as shown in FIG. 3-2.

Testing results are as shown in Table 1. The adhesion strength between the coating and the substrate are different significantly for different shapes textured on the surface of the substrate, and the adhesion strength of the coating is significantly improved with the textured patterns. The adhesion strength of the coating changes with the shape of the textured patterns. The adhesion strength of the channel-shaped textured patterns is at a maximum value 57 MPa. The adhesion strength of the hexagonal textured patterns is at an intermediate value 46 MPa. The adhesion strength of the square textured patterns is at a minimum value 33 MPa.

TABLE 1 Comparison of Adhesion strength of Coating for Different Textured Patterns Pattern shape Channel shape Square Hexagon Adhesion strength 57 MPa 33 MPa 46 MPa

In addition to the fact of the shape of the textured pattern, the adhesion strength changes with a density of the same textured pattern. A ratio of the area of the textured patterns on the surface of the substrate or the coating to the area of the substrate or the coating indicates the density of the textured patterns. In order to measure an influence of the density of the textured patterns on the adhesion strength, a density of the square textured patterns is selected, and fatigue testing is performed on the prepared square textured patterns at different densities. A testing machine used is a normal testing machine. Testing results are as shown in FIG. 4, which shows a change of adhesion strength of the coating with a grid texturing density. It can be seen that the adhesion strength of the coating changes with the texturing density, and the adhesion strength shows a trend of rising first and then falling. The texturing density has an optimal value. The adhesion strength of the coating is best in a case that the density of the square textured patterns is 30%.

It can be seen from the comparative example and the embodiments described above that the adhesion strength of the sprayed coating is changed by changing the shape of the textured patterns with the method in the present disclosure. The adhesion strength of the sprayed coating can change with the shape of the textured patterns. As compared with the existing texturing method for improving the strength of the coating, the parameter of the textured patterns is optimized. In the present disclosure, a laser texturing method is used for controlling a parameter of a laser process, to obtain textured geometrical patterns with some dimensions arranged regularly at a density on the surface of the substrate. The method, as a processing before spraying, improves a bonding force between the coating and the substrate, so that the sprayed coating can be applied into the engineering practices with a long service life.

A structure for improving adhesion strength of a coating is further provided in the present disclosure, which includes a substrate, textured patterns having at least one type of pattern prepared on the substrate and a coating sprayed on the textured patterns. The textured patterns may be in a shape of one of a square, a channel shape and a hexagon, or a combination thereof. The substrate is made of stainless steel, and the coating is a NiCrBSi coating.

The spraying process parameter is regulated below with taking different pattern dimensions of single-shaped textured patterns as parameters. The spraying process parameter is regulated with taking a depth, a diameter and a distance of the patterns as parameters, which is described in the following embodiment in detail.

Fourth Embodiment

A method for improving adhesion strength of a coating is provided in the present embodiment, in which, a depth, a diameter and a distance of textured patterns are regulated to improve the adhesion strength of the coating. The depth of the textured pattern is 35 μm. The method includes the following steps S42 and S43 in addition to the same steps as the above embodiment.

In step S42, textured patterns are prepared. The patterns with the depth of 35 μm are textured on a surface of a substrate using a laser process based on bionics.

In step S43, a parameter is regulated. A distance of the textured patterns and a spraying process parameter are regulated based on the depth of the textured patterns formed in step S42 in conjunction with different diameters, so that the different textured patterns have the same processing density.

In a case that the diameter of the textured pattern is 40 μm and the distance of the textured patterns is 60 μm, a laser power is 16 W, a scanning speed is 700 mm/s, a frequency is 20 HZ, and the number of processing is 1.

In a case that the diameter of the textured pattern is 50 μm and the distance of the textured patterns is 75 μm, a laser power is 16 W, a scanning speed is 700 mm/s, a frequency is 20 HZ, and the number of processing is 1.

In a case that the diameter of the textured pattern is 60 μm and the distance of the textured patterns is 90 μm, a laser power is 16 W, a scanning speed is 700 mm/s, a frequency is 20 HZ, and the number of processing is 1.

Fifth Embodiment

A method for improving adhesion strength of a coating is provided according to the embodiment of the present disclosure, in which, a depth, a diameter and a distance of textured patterns are regulated to improve the adhesion strength of the coating. The depth of the textured patterns is 55 μm. The method includes the following steps S52 and S53 in addition to the same steps as the above embodiment.

In step S52, textured patterns are prepared. The patterns with the depth of 55 μm are textured on a surface of a substrate using a laser process based on bionics.

In step S53, a parameter is regulated. A distance of the textured patterns and a spraying process parameter are regulated based on the depth of the textured patterns formed in step S52 in conjunction with different diameters, so that the different textured patterns have the same processing density.

In a case that the diameter of the textured pattern is 40 μm and the distance of the textured patterns is 60 μm, a laser power is 12 W, a scanning speed is 800 mm/s, a frequency is 20 HZ, and the number of processing is 2.

In a case that the diameter of the textured pattern is 50 μm and the distance of the textured patterns is 75 μm, a laser power is 12 W, a scanning speed is 800 mm/s, a frequency is 20 HZ, and the number of processing is 2.

In a case that the diameter of the textured pattern is 60 μm and the distance of the textured patterns is 90 μm, a laser power is 12 W, a scanning speed is 800 mm/s, a frequency is 20 HZ, and the number of processing is 2.

Sixth Embodiment

A method for improving adhesion strength of a coating is provided according to the embodiment of the present disclosure, in which, a depth, a diameter and a distance of textured patterns are regulated to improve the adhesion strength of the coating. The depth of the textured patterns is 75 μm. The method includes the following steps S62 and S63 in addition to the same steps as the above embodiment.

In step S62, textured patterns are prepared. The patterns with the depth of 75 μm are textured on a surface of a substrate using a laser process based on bionics.

In step S63, a parameter is regulated. A distance of the textured patterns and a spraying process parameter are regulated based on the depth of the textured patterns formed in step S62 in conjunction with different diameters, so that the different textured patterns have the same processing density.

In a case that the diameter of the textured pattern is 40 μm and the distance of the textured patterns is 60 μm, a laser power is 14 W, a scanning speed is 600 mm/s, a frequency is 20 HZ, and the number of processing is 2.

In a case that the diameter of the textured pattern is 50 μm and the distance of the textured patterns is 75 μm, a laser power is 14 W, a scanning speed is 600 mm/s, a frequency is 20 HZ, and the number of processing is 2.

In a case that the diameter of the textured pattern is 60 μm and the distance of the textured patterns is 90 μm, a laser power is 14 W, a scanning speed is 600 mm/s, a frequency is 20 HZ, and the number of processing is 2.

Seventh Embodiment

A method for improving adhesion strength of a coating is provided according to the embodiment of the present disclosure, in which, a depth, a diameter and a distance of textured patterns are regulated to improve the adhesion strength of the coating. The depth of the textured pattern is 95 μm. The method includes the following steps S72 and S73 in addition to the same steps as the above embodiment.

In step S72, textured patterns are prepared. The patterns with the depth of 95 μm are textured on a surface of a substrate using a laser process based on bionics.

In step S73, a parameter is regulated. A distance of the textured patterns and a spraying process parameter are regulated based on the depth of the textured patterns formed in step S72 in conjunction with different diameters, so that the different textured patterns have the same processing density.

In a case that the diameter of the textured pattern is 40 μm and the distance of the textured patterns is 60 μm, a laser power is 16 W, a scanning speed is 600 mm/s, a frequency is 20 HZ, and the number of processing is 2.

In a case that the diameter of the textured pattern is 50 μm and the distance of the textured patterns is 75 μm, a laser power is 16 W, a scanning speed is 600 mm/s, a frequency is 20 HZ, and the number of processing is 2.

In a case that the diameter of the textured pattern is 60 μm and the distance of the textured patterns is 90 μm, a laser power is 16 W, a scanning speed is 600 mm/s, a frequency is 20 HZ, and the number of processing is 2.

Eighth Embodiment

A method for improving adhesion strength of a coating is provided according to the embodiment of the present disclosure, in which, a depth, a diameter and a distance of textured patterns are regulated to improve the adhesion strength of the coating. The depth of the textured pattern is 115 μm. The method includes the following steps S82 and S83 in addition to the same steps as the above embodiment.

In step S82, textured patterns are prepared. The patterns with the depth of 115 μm are textured on a surface of a substrate using a laser process based on bionics.

In step S83, a parameter is regulated. A distance of the textured patterns and a spraying process parameter are regulated based on the depth of the textured patterns formed in step S82 in conjunction with different diameters, so that the different textured patterns have the same processing density.

In a case that the diameter of the textured pattern is 40 μm and the distance of the textured patterns is 60 μm, a laser power is 18 W, a scanning speed is 500 mm/s, a frequency is 20 HZ, and the number of processing is 2.

In a case that the diameter of the textured pattern is 50 μm and the distance of the textured patterns is 75 μm, a laser power is 18 W, a scanning speed is 500 mm/s, a frequency is 20 HZ, and the number of processing is 2.

In a case that the diameter of the textured pattern is 60 μm and the distance of the textured patterns is 90 μm, a laser power is 18 W, a scanning speed is 500 mm/s, a frequency is 20 HZ, and the number of processing is 2.

In the above embodiments, a list of the process parameters is as shown in Table 2 for different structure parameters of the textured patterns.

TABLE 2 Comparison of Process Parameters for Different Structure Parameters Parameters of textured patterns Power Scanning The number (F(D)-[H]-<L>) (W) speed of scanning F40-35-60, F50-35-75, F60-35-90 16 700 1 F40-55-60, F50-55-75, F60-55-90 12 800 2 F40-75-60, F50-75-75, F60-75-90 14 600 2 F40-95-60, F50-95-75, F60-95-90 16 600 2 F40-115-60, F50-115-75, F60-115-90 18 500 2

In the above Table, F denotes that a material of the substrate is FV520B, D denotes the diameter, H denotes the depth, and L denotes the distance.

Comparative Example

The tensile test is performed after the coating is sprayed on the textured patterns with different depths prepared in the above embodiments. The adhesion strength is indicated by a ratio of a force under which the coating fractures from the substrate to the area of the coating.

In the comparative experiment, the fourth embodiment, the sixth embodiment and the eighth embodiment are selected as the comparative examples. The depth of the textured patterns in the fourth embodiment is 35 μm, the form of the textured patterns with the diameter of 40 μm is as shown in FIG. 5-1, the form of the textured patterns with the diameter of 50 μm is as shown in FIG. 5-2, and the form of the textured patterns with the diameter of 60 μm is as shown in FIG. 5-3. The depth of the textured patterns in the sixth embodiment is 75 μm, the form of the textured patterns with the diameter of 40 μm is as shown in FIG. 6-1, the form of the textured patterns with the diameter of 50 μm is as shown in FIG. 6-2, and the form of the textured patterns with the diameter of 60 μm is as shown in FIG. 6-3. The depth of the textured patterns in the eighth embodiment is 115 μm, the form of the textured patterns with the diameter of 40 μm is as shown in FIG. 7-1, the form of the textured patterns with the diameter of 50 μm is as shown in FIG. 7-2, and the form of the textured patterns with the diameter of 60 μm is as shown in FIG. 7-3.

The experiment results of the tensile tests performed for the above selected comparative examples are as shown in FIG. 8 and FIG. 9. FIG. 8 is a curve diagram of comparison of adhesion strength of the sprayed coating for different textured patterns. It can be seen from the curve diagram that, in a case that the depth is 75 μm, the adhesion strength is at a maximum value whether the diameter is 40 μm, 50 μm or 60 μm. In a case that the depth is less than 75 μm, the adhesion strength is directly proportional to the depth, that is, the adhesion strength increases with an increase in the depth. In a case that the depth is greater than 75 μm, the adhesion strength is inversely proportional to the depth, that is, the adhesion strength decreases with the increase in the depth.

FIG. 9 is a curve diagram of changes of contact area and the adhesion strength of the sprayed coating with an increase in a depth of the textured patterns. It can be seen from the curve diagram that in a case that the depth is 75 μm, the adhesion strength is at the maximum value. In a case that the depth is less than 75 μm, the adhesion strength is directly proportional to the depth, that is, the adhesion strength increases with an increase in the depth. In a case that the depth is greater than 75 μm, the adhesion strength is inversely proportional to the depth, that is, the adhesion strength decreases with the increase in the depth. The contact area is always directly proportional to the depth, that is, the contact area increases with an increase in the depth. The line of contact area and the line of bonding strength have an intersection at a point of a depth between 80 μm to 90 μm

In the above diagram, D denotes the diameter, H denotes the depth and L denotes the distance.

The spraying process parameter is regulated below with taking a single pattern dimension of a single shape of textured patterns as a parameter, which is described in the following embodiment in detail.

Ninth Embodiment

A method for improving adhesion strength of a coating is provided in the present embodiment, in which, a distance of textured patterns is regulated to improve adhesion strength of the coating. The pattern shape is a circle, and a distance of the patterns is 30 μm, 50 μm, 70 μm, 90 μm or 110 μm, and a diameter of the pattern is 80 μm. The method includes step S92 and S93 in addition the same steps as the above embodiment.

In step S92, textured patterns are prepared. Circular patterns are textured on the surface of the substrate using a laser process based on bionics, to form textured patterns with the distance of 30 μm, 50 μm, 70 μm, 90 μm or 110 μm and a diameter of 80 μm.

In step S93, a parameter is regulated. A spraying process parameter is regulated based on the distance of the textured patterns formed in step S92 and the diameter of the single circular pattern, so that the different textured patterns have the same processing depth. For the textured patterns with the distance of 30 μm, 50 μm, 70 μm, 90 μm or 110 μm and a diameter of 80 μm, a laser power is 16 W, a scanning speed is 800 mm/s, and the number of processing is 1.

Comparative Example

The tensile test is performed after the coating is sprayed on the textured patterns with different distances prepared in the above embodiment. The adhesion strength is indicated by a ratio of a force under which the coating fractures from the substrate to the area of the coating.

Formation of the sprayed coating for the textured patterns with the distance of 30 μm is as shown in FIG. 10-1, and deposition of sprayed particles is as shown in FIG. 10-2. Formation of the sprayed coating for the textured patterns with the distance of 50 μm is as shown in FIG. 11-1, and deposition of sprayed particles is as shown in FIG. 11-2. Formation of the sprayed coating for the textured patterns with the distance of 70 μm is as shown in FIG. 12-1, and deposition of sprayed particles is as shown in FIG. 12-2. Formation of the sprayed coating for the textured patterns with the distance of 90 μm is as shown in FIG. 13-1, and deposition of the sprayed particles is as shown in FIG. 13-2. Formation of the sprayed coating for the textured patterns with the distance of 110 μm is as shown in FIG. 14-1, and deposition of sprayed particles is as shown in FIG. 14-2.

The testing results are as shown in FIG. 15. Adhesion strength between the coating and the substrate are significantly different for different distances of the same circular textured patterns. The adhesion strength of the coating changes with the distance. The adhesion strength is inversely proportional to the distance of the patterns. The adhesion strength decreases with an increase in the distance of the patterns. The adhesion strength increases with a decrease in the distance of the patterns.

A structure for improving adhesion strength of a coating is further provided in the present disclosure, which includes a substrate, circular textured patterns prepared on the substrate, and a coating sprayed on the textured patterns. A diameter of the textured pattern is 80 μm, and a distance of the patterns is at least one of 30 μm, 50 μm, 70 μm, 90 μm or 110 μm.

The substrate is made of stainless steel, and the coating is a NiCrBSi ceramic coating.

Tenth Embodiment

A method for improving adhesion strength of a coating is provided in the present embodiment, in which, a recess diameter of textured patterns is regulated to improve the adhesion strength of the coating. A pattern shape is a circle, and a distance of the patterns is 70 μm, a diameter of the pattern is 40 μm, 60 μm, 80 μm, 100 μm or 120 μm. The method includes the following steps S102 and S103 in addition to the same steps as the above embodiment.

In step S102, textured patterns are prepared. Circular patterns are textured on a surface of a substrate using a laser process based on bionics.

In step S103, a parameter is regulated. A spraying process parameter and a parameter of the textured patterns are regulated based on the textured patterns formed in step S102, to obtain textured patterns with a diameter of 40 μm, 60 μm, 80 μm, 100 μm or 120 μm and a distance of 70 μm. A laser power is 16 W, a scanning speed is 800 mm/s, and the number of processing is 1.

Comparative Example

Formation of the sprayed coating for the textured pattern with the diameter of 40 μm is as shown in FIG. 10-1, and deposition of sprayed particles is as shown in FIG. 10-2. Formation of the sprayed coating for the textured pattern with the diameter of 60 μm is as shown in FIG. 11-1, and deposition of sprayed particles is as shown in FIG. 11-2. Formation of the sprayed coating for the textured pattern with the diameter of 80 μm is as shown in FIG. 12-1, and deposition of the sprayed particles is as shown in FIG. 12-2. Formation of the sprayed coating for the textured pattern with the diameter of 100 μm is as shown in FIG. 13-1, and deposition of sprayed particles is as shown in FIG. 13-2. Formation of the sprayed coating for the textured pattern with the diameter of 120 μm is as shown in FIG. 14-1, and deposition of sprayed particles is as shown in FIG. 14-2.

The testing results are as shown in FIG. 16. Adhesion strength between the coating and the substrate are different significantly for different diameters of the same circular textured patterns. The adhesion strength is at a minimum value 33 MPa in a case that the diameter is 40 μm. The adhesion strength is at a maximum value 43 MPa in a case that the diameter is 120 μm. The adhesion strength is 41 MPa in a case that the diameter is 60 μm. The adhesion strength is 42 MPa in a case that the diameter is 80 μm. The adhesion strength is 40.5 MPa in a case that the diameter is 100 μm. The adhesion strength is directly proportional to the diameter in a case that the diameter ranges from 40 μm to 60 μm. The adhesion strength is directly proportional to the diameter in a case that the diameter ranges from 60 μm to 80 μm. A slope of a directly-proportional line in a case that the diameter ranges from 60 μm to 80 μm is less than a slope of a directly-proportional line in a case that the diameter ranges from 40 μm to 60 μm. The adhesion strength is inversely proportional to the diameter in a case that the diameter ranges from 80 μm to 100 μm. The adhesion strength is directly proportional to the diameter in a case that the diameter ranges from 100 μm to 120 μm.

A structure for improving adhesion strength of a coating is further provided according to the embodiment of the present disclosure, which includes a substrate, circular textured patterns prepared on the substrate, and a coating sprayed on the textured patterns. A distance of the textured patterns is 70 μm, and a diameter of the pattern is at least one of 40 μm, 60 μm, 80 μm, 100 μm or 120 μm. The substrate is made of stainless steel, and furthermore is made of FV520B, and the coating is a NiCrBSi ceramic coating.

Eleventh Embodiment

A method for improving adhesion strength of a coating is provided in the present embodiment, in which, a width of a channel-shaped textured pattern is regulated to improve the adhesion strength of the coating. The method includes the following steps S112 and S113 in addition to the same steps as the above embodiment.

In step S112, textured patterns are prepared. Channel-shaped patterns are textured on a surface of a substrate using a laser process based on bionics.

In step S113, a parameter is regulated. A spraying process parameter and a parameter of the textured patterns are regulated based on the textured patterns formed in step S112, to obtain textured patterns with a width of 10 μm and a distance of 60 μm, textured patterns with a width of 15 μm and a distance of 60 μm, textured patterns with a width of 20 μm and a distance of 60 μm, or textured patterns with a width of 30 μm and a distance of 60 μm.

For the channel-shaped textured patterns with the shape parameters, a laser power is 14 W, a scanning speed is 800 mm/s, and the number of processing is 2.

Comparative Example

The tensile test is performed after the coating is sprayed on the textured patterns with different widths prepared in the above embodiment. The adhesion strength is indicated by a ratio of a force under which the coating fractures from the substrate to the area of the coating.

The testing results are as shown in FIG. 17. Adhesion strength between the coating and the substrate are different significantly for different widths of the same channel-shaped textured patterns. Comparison of the adhesion strength corresponding to the different widths is as shown in the following Table.

TABLE 3 Comparison of Adhesion strength corresponding to Different Widths Width of a channel shape 10 μm 15 μm 20 μm 30 μm Adhesion strength 25.5 MPa 32 MPa 46 MPa 51 MPa

The adhesion strength is at a minimum value 25.5 MPa in a case that the width of the channel-shaped textured pattern is 10 μm. The adhesion strength is at a maximum value 51 MPa in a case that the width of the channel-shaped textured pattern is 30 μm. The adhesion strength is 32 MPa in a case that the width is 15 μm. The adhesion strength is 46 MPa in a case that the width is 20 μm. In a case that the width ranges from 10 μm to 20 μm, the adhesion strength is directly proportional to the width, as a first directly-proportional line. In a case that the width ranges from 20 μm to 30 μm, the adhesion strength is directly proportional to the width, as a second directly-proportional line. A slope of the first directly-proportional line is greater than a slope of the second directly-proportional line.

A structure for improving adhesion strength of a coating is provided according to the embodiment of the present disclosure, which includes a substrate, channel-shaped textured patterns prepared on the substrate, and a coating sprayed on the channel-shaped textured patterns. A distance of the textured patterns is 60 μm, and a width of the channel-shaped pattern is at least one of 10 μm, 15 μm, 20 μm or 30 μm. The substrate is made of stainless steel, and furthermore is made of FV520B, and the coating is a NiCrBSi ceramic coating.

Twelfth Embodiment

A method for improving adhesion strength of a coating is provided in the present embodiment, in which, a length of a channel-shaped textured pattern is regulated to improve the adhesion strength of the coating. The method includes the following steps S122 and S123 in addition to the same steps as the above embodiment.

In step S122, textured patterns are prepared. Channel-shaped patterns are textured on a surface of a substrate using a laser process based on bionics.

In step S123, a parameter is regulated. A spraying process parameter and a parameter of the textured patterns are regulated based on the textured patterns formed in step S122, to obtain textured patterns with a length of 20 μm, a width of 15 μm and a distance of 60 μm, textured patterns with a length of 35 μm, a width of 15 μm and a distance of 60 μm, textured patterns with a length of 45 μm, a width of 15 μm and a distance of 60 μm, or textured patterns with a length of 55 μm, a width of 15 μm and a distance of 60 μm.

For the channel-shaped textured patterns with the parameters, a laser power is 16 W, a scanning speed is 1000 mm/s, and the number of processing is 2.

Comparative Example

The tensile test is performed after the coating is sprayed on the textured patterns with different lengths prepared in the above embodiment. The adhesion strength is indicated by a ratio of a force under which the coating fractures from the substrate to the area of the coating.

The testing results are as shown in FIG. 18. Adhesion strength between the coating and the substrate are different significantly for different lengths of the same channel-shaped textured patterns. Comparison of the adhesion strength corresponding to the different lengths is as shown in the following Table.

TABLE 4 Comparison of Adhesion strength corresponding to Different Lengths Length of a channel shape 20 μm 30 μm 45 μm 55 μm Adhesion strength 32 MPa 38 MPa 55 MPa 47 MPa

In a case that the width of the channel-shaped textured pattern is fixed, the adhesion strength is at a minimum value 32 MPa in a case that the length of the channel-shaped textured pattern is 20 μm. The adhesion strength is at a maximum value 55 MPa in a case that the length of the channel-shaped textured pattern is 45 μm. The adhesion strength is 38 MPa in a case that the length of the channel-shaped textured pattern is 30 μm. The adhesion strength is 47 MPa in a case that the length of the channel-shaped textured pattern is 55 μm. In a case that the length ranges from 20 μm to 45 μm, the adhesion strength is directly proportional to the length, as a directly-proportional line. In a case that the length ranges from 45 μm to 55 μm, the adhesion strength is inversely proportional to the length, as an inversely-proportional line.

A structure for improving adhesion strength of a coating is further provided according to the embodiment of the present disclosure, which includes a substrate, channel-shaped textured patterns prepared on the substrate, and a coating sprayed on the channel-shaped textured patterns. A distance of the textured patterns is 60 μm, and a width of the channel-shaped pattern is 15 μm, and the length of the channel-shaped pattern is at least one of 20 μm, 30 μm, 45 μm or 55 μm. The substrate is made of stainless steel, and furthermore is made of FV520B, and the coating is a NiCrBSi ceramic coating.

Thirteenth Embodiment

A method for improving adhesion strength of a coating is provided in the present embodiment, in which, a side length of a square textured pattern is regulated to improve the adhesion strength of the coating. The method includes the following steps S132 and S133 in addition to the same steps as the above embodiment.

In step S132, textured patterns are prepared. Square patterns are textured on a surface of a substrate using a laser process based on bionics.

In step S133, a parameter is regulated. A spraying process parameter and a parameter of the textured patterns are regulated based on the textured patterns formed in step S132, to obtain textured patterns with a side length of 20 μm and a distance of 60 μm, textured patterns with a side length of 35 μm and a distance of 60 μm, textured patterns with a side length of 55 μm and a distance of 60 μm, or textured patterns with a side length of 70 μm and a distance of 60 μm.

For the textured patterns with the shape parameters, a laser power is 15 W, a scanning speed is 900 mm/s, and the number of processing is 1.

Comparative Example

The tensile test is performed after the coating is sprayed on the textured patterns with different side lengths prepared in the above embodiment. The adhesion strength is indicated by a ratio of a force under which the coating fractures from the substrate to the area of the coating.

The testing results are as shown in FIG. 19. Adhesion strength between the coating and the substrate are different significantly for different side lengths of the same square textured patterns. Comparison of the adhesion strength corresponding to the different side lengths is as shown in the following Table.

TABLE 5 Comparison of Adhesion strength corresponding to Different Side Lengths Side length of a square 20 μm 35 μm 55 μm 70 μm Adhesion strength 28 MPa 35.5 MPa 52 MPa 55.5 MPa

The adhesion strength is at a minimum value 28 MPa in a case that the side length of the square textured pattern is 20 μm. The adhesion strength is at a maximum value 55.5 MPa in a case that the side length of the square textured pattern is 70 μm. The adhesion strength is 35.5 MPa in a case that the side length of the square textured pattern is 35 μm. The adhesion strength is 52 MPa in a case that the side length of the square textured pattern is 55 μm. It can be seen that the adhesion strength increases with an increase in the side length in a case that the side length ranges from 20 μm to 70 μm.

A structure for improving adhesion strength of a coating is further provided according to the embodiment of the present disclosure, which includes a substrate, square textured patterns prepared on the substrate, and a coating sprayed on the square textured patterns. A distance between the square textured patterns is 60 μm, and a side length of the square textured pattern is at least one of 20 μm, 35 μm, 55 μm or 70 μm. The substrate is made of stainless steel, and furthermore is made of FV520B, and the coating is a NiCrBSi ceramic coating.

Fourteenth Embodiment

A method for improving adhesion strength of a coating is provided in the present embodiment, in which, a side length of a regular-hexagonal textured pattern is regulated to improve the adhesion strength of the coating. The method includes the following steps S142 and S143 in addition to the same steps as the above embodiment.

In step S142, textured patterns are prepared. Regular-hexagonal patterns are textured on a surface of a substrate using a laser process based on bionics.

In step S143, a parameter is regulated. A spraying process parameter and a parameter of the textured patterns are regulated based on the textured patterns formed in step S142, to obtain textured patterns with a side length of 20 μm and a distance of 65 μm, textured patterns with a side length of 30 μm and a distance of 65 μm, textured patterns with a side length of 45 μm and a distance of 65 μm, or textured patterns with a side length of 60 μm and a distance of 65 μm.

For the regular-hexagonal textured patterns, a laser power is 14 W, a scanning speed is 800 mm/s, and the number of processing is 2.

Comparative Example

The tensile test is performed after the coating is sprayed on the regular-hexagonal textured patterns prepared in the above embodiment. The adhesion strength is indicated by a ratio of a force under which the coating fractures from the substrate to the area of the coating.

The testing results are as shown in FIG. 20. Adhesion strength between the coating and the substrate are different significantly for different side lengths of the same regular-hexagonal textured patterns. Comparison of the adhesion strength corresponding to the different side lengths are as shown in the following Table.

TABLE 6 Comparison of Adhesion strength corresponding to Different Side Lengths Side length of a hexagon 20 μm 30 μm 45 μm 60 μm Adhesion strength 28.5 MPa 31.5 MPa 55 MPa 53 MPa

The adhesion strength is at a minimum value 28.5 MPa in a case that the side length of the regular-hexagonal textured pattern is 20 μm. The adhesion strength is at a maximum value 55 MPa in a case that the side length of the regular-hexagonal textured pattern is 45 μm. The adhesion strength is 31.5 MPa in a case that the side length of the regular-hexagonal textured pattern is 30 μm. The adhesion strength is 53 MPa in a case that the side length of the regular-hexagonal textured pattern is 60 μm. The adhesion strength is directly proportional to the side length in a case that the side length ranges from 20 μm to 45 μm. The adhesion strength is inversely proportional to the side length in a case that the side length ranges from 45 μm to 60 μm. A slope of the directly-proportional line is greater than a slope of the inversely-proportional line.

A structure for improving adhesion strength of a coating is further provided according to the embodiment of the present disclosure, which includes a substrate, regular-hexagonal textured patterns prepared on the substrate, and a coating sprayed on the regular-hexagonal textured patterns. A distance of the regular-hexagonal textured patterns is 65 μm, and a side length of the regular-hexagonal textured pattern is at least one of 20 μm, 30 μm, 45 μm or 60 μm. The substrate is made of stainless steel, and furthermore is made of FV520B, and the coating is a NiCrBSi ceramic coating.

The spraying process parameter is regulated with taking different pattern dimensions of combination-shaped textured patterns as a parameter, which is described in the following embodiment in detail.

Fifteenth Embodiment

A method for improving adhesion strength of a coating is provided in the present embodiment, in which, a width of a channel-shaped pattern and a diameter of a circular pattern in a pattern formed by alternately combining channel shapes and circles are regulated to improve the adhesion strength of the coating. The method includes the following steps S152 and S153 in addition to the same steps as the above embodiments.

In step S152, textured patterns are prepared. Combination-shaped patterns formed by alternately combining channel shapes and circles are textured on a surface of a substrate using a laser process based on bionics.

In step S153, a parameter is regulated. A spraying process parameter and a parameter of the textured patterns are regulated based on the textured patterns formed in step S152, to obtain textured patterns formed by alternately combining the channel shapes and the circles. In the textured patterns, a distance between the channel shape and the circle adjacent to the channel shape is 60 μm, a width of the channel shape is 15 μm, and a diameter of the circle is 15 μm. Alternatively, a distance between the channel shape and the circle adjacent to the channel shape is 60 μm, a width of the channel shape is 25 μm, and a diameter of the circle is 25 μm. Alternatively, a distance between the channel shape and the circle adjacent to the channel shape is 60 μm, a width of the channel shape is 40 μm, and a diameter of the circle is 40 μm. Alternatively, a distance between the channel shape and the circle adjacent to the channel shape is 60 μm, a width of the channel shape is 60 μm, and a diameter of the circle is 60 μm.

For the textured patterns with the shape parameters, a laser power is 15 W, a scanning speed is 900 mm/s, and the number of processing is 2. The textured patterns are textured by the following steps: texturing at least three columns of circular patterns, where a preset distance is reserved between each pair of adjacent columns of circular patterns, and the preset distance is greater than a width of a channel shape to be textured; and texturing channel-shaped patterns between each pair of adjacent columns of circular patterns.

Comparative Example

The tensile test is performed on the textured patterns formed by alternately combining the circles and the channel shapes with different dimensions prepared in the above embodiment, and on a circular textured pattern and a channel-shaped textured pattern after a coating is sprayed on the respective textured patterns. The adhesion strength is indicated by a ratio of a force under which the coating fractures from the substrate to the area of the coating.

The testing results are as shown in FIG. 21 and FIG. 22. FIG. 21 is a curve diagram showing comparison of adhesion strength for the combination-shaped textured pattern, the only-circular pattern and the only-channel-shaped pattern. FIG. 22 shows adhesion strength between the coating and the substrate for the combination-shaped textured patterns formed by alternately combining the circles and the channel shapes with different dimensions. Comparison of adhesion strength for the combination-shaped textured patterns with different dimensions is as shown in the following Table.

TABLE 7 Comparison of Adhesion strength for Combination-shaped Textured Patterns with Different Dimensions Width of a channel shape 15 μm 25 μm 40 μm 60 μm Diameter of a circle 15 μm 25 μm 40 μm 60 μm Adhesion strength 28 MPa 35 MPa 48 MPa 56 MPa

In a case that the textured patterns are formed by alternately combining the circles and the channel shapes, the adhesion strength is affected by both a width of the channel shape and a diameter of the circle. Taking the above Table as an example, the adhesion strength is at a minimum value 28 MPa in a case that the width of the channel shape is 15 μm and the diameter of the circle is 15 μm. The adhesion strength is at a maximum value 56 MPa in a case that the width of the channel shape is 60 μm and the diameter of the circle is 60 μm. The adhesion strength is 35 MPa in a case that the width of the channel shape is 25 μm and the diameter of the circle is 25 μm. The adhesion strength is 48 MPa in a case that the width of the channel shape is 40 μm and the diameter of the circle is 40 μm. It can be seen that the adhesion strength increases with an increase in the width of the channel shape and an increase in the diameter of the circle in a case that the width of the channel shape ranges from 15 μm to 60 μm and the diameter of the circle ranges from 15 μm to 60 μm.

As compared with the single-shaped textured pattern, the alternate-combination-shaped textured pattern has higher adhesion strength. Comparison of adhesion strength for the only-channel-shaped textured pattern, the only-circular textured pattern, and the combination-shaped textured pattern formed by alternately combining the circles with the same dimension as the only-circular textured pattern and the channel shapes with the same dimension as the only-channel-shaped textured pattern is as shown in the following Table.

TABLE 8 Comparison of Adhesion strength for Single-Shaped Pattern and Combination-shaped Pattern with the same Dimension Adhesion strength of an only-channel-shaped pattern with a 36 MPa width of 40 μm Adhesion strength of an only-circular pattern with a 40 MPa diameter of 40 μm Adhesion strength of a combination-shaped pattern of channel 48 MPa shapes with a width of 40 μm and circles with a diameter of 40 μm

In the method provided in the present disclosure, the adhesion strength of the sprayed coating is changed by changing a combination manner of the textured patterns. For the textured patterns in an only channel shape, an only circle shape, and a shape of alternating the channel shape and the circle shape, the respective adhesion strengths of the sprayed coating are different. As compared with the existing texturing method for improving strength of the coating, the parameter of the textured patterns is optimized. In the present disclosure, a laser texturing method is used for controlling a parameter of a laser process, to obtain textured geometrical patterns with dimensions arranged regularly at a density on the surface of the substrate. As a processing before spraying, the textured patterns formed by alternately combining the channel shapes and the circles are prearranged on a surface of a material. As compared with the only-channel-shaped textured pattern and the only-circular textured pattern, a problem in the single-shaped patterns that stress is centralized in a certain direction and positions of adhesion weak points are uniform can be solved with the combination-shaped pattern. That is, in the only-channel-shaped textured patterns, weak points of the channel shapes are located at the same or similar positions of the channels, which results in easily cracking of the whole coating in a certain direction. In the combination-shaped patterns, a weak point of the channel-shaped textured pattern and a weak point of the circular textured pattern are located at different positions of the respective patterns. Therefore, the channel-shaped textured pattern and the circular textured pattern can complement with each other in a case that the channel-shaped textured pattern and the circular textured pattern are combined together, thereby improving the overall adhesion strength. A mechanism in which the strength of the sprayed coating is improved by combining the channel-shaped textured pattern and the circular textured pattern is researched by changing a characteristic of the single type of the traditional textured pattern, and an optimal parameter of the textured patterns for effectively improving adhesion strength of the coating is further researched. Therefore, the bonding force between the coating and the substrate is improved, so that the sprayed coating can be applied into the engineering practices with a long service life.

A structure for improving adhesion strength of a coating is further provided according to the embodiment of the present disclosure, which includes a substrate, textured patterns prepared on the substrate, and a coating sprayed on the textured patterns. The textured patterns include multiple columns of channel-shaped patterns and multiple columns of circular patterns. The channel-shaped pattern and the circular pattern are arranged alternately, and one column of circular patterns is arranged between each pair of adjacent columns of channel-shaped patterns. A distance between the channel shape and the circle adjacent to the channel shape in the textured patterns is 60 μm. A width of the channel shape is at least one of 15 μm, 25 μm, 40 μm or 60 μm. A diameter of the circle is at least one of 15 μm, 25 μm, 40 μm or 60 μm. The substrate is made of stainless steel, and furthermore is made of FV520B, and the coating is a NiCrBSi ceramic coating.

Sixteenth Embodiment

A method for improving adhesion strength of a coating is provided in the present embodiment, in which, a side length of a regular hexagon and a side length of a square in textured patterns formed by alternately combining regular hexagons and squares are regulated to improve the adhesion strength of the coating. The method includes the following steps S162 and S163 in addition to the same steps as the above embodiments.

In step S162, textured patterns are prepared. Combination-shaped patterns formed by combining regular hexagons and squares are textured on a surface of a substrate using a laser process based on bionics.

In step S163, a parameter is regulated. A spraying process parameter and a parameter of the textured patterns are regulated based on the textured patterns formed in step S162, to obtain textured patterns formed by alternately combining the regular hexagons and the squares. In the textured patterns, a distance between the regular hexagon and the square adjacent to the regular hexagon is 60 μm, a side length of the regular hexagon is 20 μm, and a side length of the square is 20 μm. Alternatively, a distance between the regular hexagon and the square adjacent to the regular hexagon is 60 μm, a side length of the regular hexagon is 30 μm, and a side length of the square is 30 μm. Alternatively, a distance between the regular hexagon and the square adjacent to the regular hexagon is 60 μm, a side length of the regular hexagon is 45 μm, and a side length of the square is 45 μm. Alternatively, a distance between the regular hexagon and the square adjacent to the regular hexagon is 60 μm, a side length of the regular hexagon is 60 μm, and a side length of the square is 60 μm.

For the textured patterns with the shape parameters, a laser power is 14 W, a scanning speed is 800 mm/s, and the number of processing is 2. The textured patterns are textured by: texturing at least three columns of square patterns, where a preset distance is reserved between each pair of adjacent columns of square patterns, and the preset distance is greater than a length of the longest diagonal line of a regular hexagon to be textured; and texturing one column of regular-hexagonal patterns between each pair of adjacent columns of square patterns.

Comparative Example

The tensile test is performed on the textured patterns formed by alternately combining the squares and the regular hexagons with different dimensions prepared in the above embodiment, and on an only-square pattern and an only-regular-hexagonal pattern after a coating is sprayed on the respective patterns. The adhesion strength is indicated by a ratio of a force under which the coating fractures from the substrate to the area of the coating.

The testing results are as shown in FIG. 23 and FIG. 24. FIG. 23 is a curve diagram showing comparison of adhesion strength for the combination-shaped textured pattern, the only-square pattern and the only-regular-hexagonal pattern. FIG. 24 shows adhesion strength between the coating and the substrate for the combination-shaped textured patterns formed by alternately combining the squares and the regular hexagons with different dimensions. Comparison of adhesion strength for the combination-shaped textured patterns with different dimensions is as shown in the following Table.

TABLE 9 Comparison of Adhesion strength of Combination-shaped Textured Patterns with Different Dimensions Side length of a regular hexagon 20 μm 30 μm 45 μm 60 μm Side length of a square 20 μm 30 μm 45 μm 60 μm Adhesion strength 38 MPa 46 MPa 55 MPa 68 MPa

In a case that the textured patterns are formed by alternately combining the squares and the regular hexagon, the adhesion strength is affected by both the side length of the square and the side length of the regular hexagon. Taking the above Table as an example, the adhesion strength is at a minimum value 38 MPa in a case that the side length of the regular hexagon is 20 μm and the side length of the square is 20 μm. The adhesion strength is at a maximum value 68 MPa in a case that the side length of the regular hexagon is 60 μm and the side length of the square is 60 μm. The adhesion strength is 46 MPa in a case that the side length of the regular hexagon is 30 μm and the side length of the square is 30 μm. The adhesion strength is 55 MPa in a case that the side length of the regular hexagon is 45 μm and the side length of the square is 45 μm. It can be seen that the adhesion strength increases with an increase in the side length of the regular hexagon and an increase in the side length of the square in a case that the side length of the regular hexagon ranges from 20 μm to 60 μm and the side length of the square ranges from 20 μm to 60 μm.

As compared with the single-shaped textured pattern, the alternate-combination-shaped textured pattern has higher adhesion strength. Comparison of adhesion strength for the only-regular-hexagonal textured pattern, the only-square textured pattern, and the combination-shaped textured pattern formed by alternately combining the squares with the same dimension as the only-square textured pattern and the regular hexagons with the same dimension as the only-regular-hexagonal textured pattern is as shown in the following Table.

TABLE 10 Comparison of Adhesion strength for Single-Shaped Pattern and Combination-shaped Pattern with the same Dimension Adhesion strength of an only-regular-hexagonal pattern 48 MPa with a side length of 45 μm Adhesion strength of an only-square pattern with a side 46 MPa length of 45 μm Adhesion strength of a combination-shaped pattern of regular 55 MPa hexagons with a side length of 45 μm and squares with a side length of 45 μm

In the method provided in the present disclosure, the adhesion strength of the sprayed coating is changed by changing a combination manner of the textured patterns. For the textured patterns in an only regular hexagon shape, an only square shape, and a shape of alternating the regular hexagons and the squares, the respective adhesion strengths of the sprayed coating are different. As compared with the existing texturing method for improving strength of the coating, the parameter of the textured patterns is optimized. In the present disclosure, a laser texturing method is used for controlling a parameter of a laser process, to obtain textured geometrical patterns with dimensions arranged regularly at a density on the surface of the substrate. As a processing before spraying, the textured patterns formed by alternately combining the regular hexagons and the squares are prearranged on a surface of a material. As compared with the only-regular-hexagonal textured pattern and the only-square textured pattern, a problem in the single-shaped patterns that stress is centralized in a certain direction and positions of adhesion weak points are uniform can be solved with the combination-shaped pattern. That is, in the only-regular-hexagonal textured patterns, weak points of the regular hexagons are located at the same or similar positions of the regular hexagons, which results in easily cracking of the whole coating in a certain direction. In the combination-shaped patterns, a weak point of the regular-hexagonal textured pattern and a weak point of the square textured pattern are located at different positions of the respective patterns. Therefore, the regular-hexagonal textured pattern and the square textured pattern can complement with each other in a case that the regular-hexagonal textured pattern and the square textured pattern are combined together, thereby improving the overall adhesion strength. A mechanism in which the strength of the sprayed coating is improved by combining the regular-hexagonal textured patterns and the square textured patterns is researched by changing a characteristic of the single type of the traditional textured pattern, and an optimal parameter of the textured patterns for effectively improving adhesion strength of the coating is further researched. Therefore, the bonding force between the coating and the substrate is improved, so that the sprayed coating can be applied into the engineering practices with a long service life.

A structure for improving adhesion strength of a coating is further provided according to the embodiment of the present disclosure, which includes a substrate, textured patterns prepared on the substrate, and a coating sprayed on the textured patterns. The textured patterns include multiple columns of regular-hexagonal patterns and multiple columns of square patterns. The regular-hexagonal pattern and the square pattern are arranged alternately, and one column of square patterns is arranged between each pair of adjacent columns of regular-hexagonal patterns. A distance between the regular-hexagon and the square adjacent to the regular-hexagon in the textured patterns is 60 μm. A side length of the regular hexagon is at least one of 20 μm, 30 μm, 45 μm or 60 μm. A side length of the square is at least one of 15 μm, 30 μm, 45 μm or 60 μm. The substrate is made of stainless steel, and furthermore is made of FV520B, and the coating is a NiCrBSi ceramic coating.

Seventeenth Embodiment

A method for improving adhesion strength of a coating is provided in the present embodiment, in which, a side length of a regular-hexagonal pattern and a diameter of a circular pattern in textured patterns formed by alternately combining regular hexagons and circles are regulated to improve adhesion strength of the coating. The method includes the following steps S172 and S173 in addition to the same steps as the above embodiments.

In step S172, textured patterns are prepared. Combination-shaped patterns formed by alternately combining regular hexagons and circles are textured on a surface of a substrate using a laser process based on bionics.

In step S173, a parameter is regulated. A spraying process parameter and a parameter of the textured patterns are regulated based on the textured patterns formed in step S172, to obtain textured patterns formed by alternately combining the regular hexagons and the circles. In the textured patterns, a distance between the regular hexagon and the circle adjacent to the regular hexagon is 60 μm, a side length of the regular hexagon is 20 μm, and a diameter of the circle is 15 μm. Alternatively, a distance between the regular hexagon and the circle adjacent to the regular hexagon is 60 μm, a side length of the regular hexagon is 35 μm, and a diameter of the circle is 25 μm. Alternatively, a distance between the regular hexagon and the circle adjacent to the regular hexagon is 60 μm, a side length of the regular hexagon is 55 μm, and a diameter of the circle is 40 μm. Alternatively, a distance between the regular hexagon and the circle adjacent to the regular hexagon is 60 μm, a side length of the regular hexagon is 70 μm, and a diameter of the circle is 60 μm.

For the textured patterns with the shape parameters, a laser power is 15 W, a scanning speed is 900 mm/s, and the number of processing is 2. The textured patterns are textured by: texturing at least three columns of circular patterns, where a preset distance is reserved between each pair of adjacent columns of circular patterns, and the preset distance is greater than a length of the longest diagonal line of the regular hexagon to be textured; and texturing regular-hexagonal patterns between each pair of adjacent columns of circular patterns.

Comparative Example

The tensile test is performed on the combination-shaped textured patterns formed by alternately combining the circles and the regular hexagons with different dimensions prepared in the above embodiment, and on an only-circular pattern and an only-regular-hexagonal pattern after a coating is sprayed on the respective textured patterns. The adhesion strength is indicated by a ratio of a force under which the coating fractures from the substrate to the area of the coating.

The testing results are as shown in FIG. 25 and FIG. 26. FIG. 25 is a curve diagram showing comparison of adhesion strength for the combination-shaped textured pattern, the only-circular pattern and the only-regular-hexagonal pattern. FIG. 26 shows adhesion strength between the coating and the substrate for the combination-shaped textured patterns formed by alternately combining the circles and the regular hexagons with different dimensions. Comparison of adhesion strength for the combination-shaped textured patterns with different dimensions is as shown in the following Table.

TABLE 11 Comparison of Adhesion strength for Combination-shaped Textured Patterns with Different Dimensions Side length of a regular hexagon 20 μm 35 μm 55 μm 70 μm Diameter of a circle 15 μm 25 μm 40 μm 60 μm Adhesion strength 35 MPa 43 MPa 56 MPa 64 MPa

In a case that the textured patterns are formed by combining the circles and the regular hexagons, the adhesion strength is affected by both the side length of the regular hexagon and the diameter of the circle. Taking the above Table as an example, the adhesion strength is at a minimum value 35 MPa in a case that the side length of the regular hexagon is 20 μm and the diameter of the circle is 15 μm. The adhesion strength is at a maximum value 64 MPa in a case that the side length of the regular hexagon is 70 μm and the diameter of the circle is 60 μm. The adhesion strength is 43 MPa in a case that the side length of the regular hexagon is 35 μm and the diameter of the circle is 25 μm. The adhesion strength is 56 MPa in a case that the side length of the regular hexagon is 55 μm and the diameter of the circle is 40 μm. It can be seen that the adhesion strength increases with an increase in the side length of the regular hexagon and an increase in the diameter of the circle in a case that the side length of the regular hexagon ranges from 20 μm to 70 μm and the diameter of the circle ranges from 15 μm to 60 μm.

As compared with the single-shaped textured pattern, the alternate-combination-shaped textured pattern has higher adhesion strength. Comparison of adhesion strength for the only-regular-hexagonal textured pattern, the only-circular textured pattern and the combination-shaped textured pattern formed by alternately combing the circles with the same dimension as the only-circular textured pattern and the regular hexagons with the same dimension as the only-regular-hexagonal textured pattern is as shown in the following Table.

TABLE 12 Comparison of Adhesion strength for Single-Shaped Pattern and Combination-shaped Pattern with the same Dimension Adhesion strength of an only-regular-hexagonal pattern with 52 MPa a side length of 55 μm Adhesion strength of an only-circular pattern with a 40 MPa diameter of 40 μm Adhesion strength of a combination-shaped pattern of regular 56 MPa hexagons with a side length of 55 μm and circles with a diameter of 40 μm

In the method provided in the present disclosure, the adhesion strength of the sprayed coating is changed by changing a combination manner of the textured patterns. For the textured patterns in an only regular hexagon shape, an only circle shape and a shape of alternating the regular hexagons and the circles, the respective adhesion strengths of the sprayed coating are different. As compared with the existing texturing method for improving strength of the coating, the parameter of the textured patterns is optimized. In the present disclosure, a laser texturing method is used for controlling a parameter of the laser process, to obtain textured geometrical patterns with dimensions and arranged regularly at a density on the surface of the substrate. As a processing before spraying, the textured patterns formed by alternately combining the regular hexagons and the circles are prearranged on a surface of a material. As compared with the only-regular-hexagonal textured pattern and the only-circular textured pattern, a problem in the single-shaped patterns that stress is centralized in a certain direction and positions of adhesion weak points are uniform can be solved with the combination-shaped patterns. That is, in the only-regular-hexagonal textured patterns, the weak points in the regular hexagons are located at the same or similar positions of the regular hexagons, which results in easily cracking of the whole coating in a certain direction. In the combination-shaped patterns, a weak point in the regular-hexagonal textured pattern and a weak point of the circular textured pattern are located at different positions of the respective patterns. Therefore, the regular-hexagonal textured pattern and the circular textured pattern can complement with each other in a case that the regular-hexagonal textured pattern and the circular textured pattern are combined together, thereby improving the overall adhesion strength. A mechanism in which the strength of the sprayed coating is improved by combining the regular-hexagonal textured pattern and the circular textured pattern is researched by changing a characteristic of the single type of the traditional textured pattern, and an optimal parameter of the textured patterns for effectively improving adhesion strength of the coating is further researched. Therefore, the bonding force between the coating and the substrate is improved, so that the sprayed coating can be applied into the engineering practices with a long service life.

A structure for improving adhesion strength of a coating is further provided according to the embodiment of the present disclosure, which includes a substrate, textured patterns prepared on the substrate, and a coating sprayed on the textured patterns. The textured patterns include multiple columns of regular-hexagonal patterns and multiple columns of circular patterns. The regular-hexagonal pattern and the circular pattern are arranged alternately. One column of circular patterns is arranged between each pair of adjacent columns of regular-hexagonal patterns, and one column of regular-hexagonal patterns is arranged between each pair of adjacent columns of circular patterns. A distance between the regular hexagon and the circle adjacent to the regular hexagon in the textured patterns is 60 μm. A side length of the regular hexagon is at least one of 20 μm, 35 μm, 55 μm or 70 μm. A diameter of the circle is at least one of 15 μm, 25 μm, 40 μm or 60 μm. The substrate is made of stainless steel, and furthermore is made of FV520B, and the coating is a NiCrBSi ceramic coating.

Eighteenth Embodiment

A method for improving adhesion strength of a coating is provided in the present embodiment, in which, a side length of a square and a diameter of a circle in textured patterns formed by alternately combining squares and circles are regulated to improve the adhesion strength of the coating. The method includes the following steps S182 and S183 in addition to the same steps as the above embodiments.

In step S182, textured patterns are prepared. Combination-shaped patterns formed by alternately combining squares and circles are textured on a surface of a substrate using a laser process based on bionics.

In step S183, a parameter is regulated. A spraying process parameter and a parameter of the textured patterns are regulated based on the textured patterns formed in step S182, to obtain textured patterns formed by alternately combining the squares and the circles. In the textured patterns, a distance between the square and the circle adjacent to the square is 60 μm, a side length of the square is 20 μm, and a diameter of the circle is 15 μm. Alternatively, a distance between the square and the circle adjacent to the square is 60 μm, a side length of the regular hexagon is 35 μm, and a diameter of the circle is 25 μm. Alternatively, a distance between the square and the circle adjacent to the square is 60 μm, a side length of the square is 55 μm, and a diameter of the circle is 40 μm. Alternatively, a distance between the square and the circle adjacent to the square is 60 μm, a side length of the square is 70 μm, and a diameter of the circle is 60 μm.

For the textured patterns with the shape parameters, a laser power is 15 W, a scanning speed is 900 mm/s, and the number of processing is 2. The textured patterns are textured by: texturing at least three columns of circular patterns, where a preset distance is reserved between each pair of adjacent columns of circular patterns, and the preset distance is greater than a side length of the square to be textured; and texturing square patterns between each pair of adjacent columns of circular patterns.

Comparative Example

The tensile test is performed on the textured patterns formed by alternately combining the circles and the squares with different dimensions prepared in the above embodiment, and on an only-circular pattern and an only-square pattern after a coating is sprayed on the respective patterns. The adhesion strength is indicated by a ratio of a force under which the coating fractures from the substrate to the area of the coating.

The testing results are as shown in FIG. 27 and FIG. 28. FIG. 27 is a curve diagram showing comparison of adhesion strength for the combination-shaped textured pattern, the only-circular pattern and the only-square pattern. FIG. 28 shows adhesion strength between the coating and the substrate for the combination-shaped textured patterns formed by alternately combining the circles and the squares with different dimensions. Comparison of adhesion strength for the combination-shaped textured patterns with different dimensions is as shown in the following Table.

TABLE 13 Comparison of Adhesion strength for Combination-shaped Textured Patterns with Different Dimensions Side length of a square 20 μm 35 μm 55 μm 70 μm Diameter of a circle 15 μm 25 μm 40 μm 60 μm Adhesion strength 30 MPa 39 MPa 52 MPa 62 MPa

In a case that the textured patterns are formed by combining the circles and the squares, the adhesion strength is affected by both the side length of the square and the diameter of the circle. Taking the above Table as an example, the adhesion strength is at a minimum value 30 MPa in a case that the side length of the square is 20 μm and the diameter of the circle is 15 μm. The adhesion strength is at a maximum value 62 MPa in a case that the side length of the square is 70 μm and the diameter of the circle is 60 μm. The adhesion strength is 39 MPa in a case that the side length of the square is 35 μm and the diameter of the circle is 25 μm. The adhesion strength is 52 MPa in a case that the side length of the square is 55 μm and the diameter of the circle is 40 μm. It can be seen that the adhesion strength increases with an increase in the side length of the square and an increase in the diameter of the circle in a case that the side length of the square ranges from 20 μm to 70 μm and the diameter of the circle ranges from 15 μm to 60 μm.

As compared with the single-shaped textured patterns, the alternate-combination-shaped textured pattern has higher adhesion strength. Comparison of adhesion strength for the only-square textured pattern, the only-circular textured pattern and the combination-shaped textured pattern formed by alternately combing the circles with the same dimension as the only-circular textured pattern and the squares with the same dimension as the only-square textured pattern is as shown in the following Table.

TABLE 14 Comparison of Adhesion strength for Single-Shaped Pattern and Combination-shaped Pattern with the same Dimension Adhesion strength of an only-square pattern with a 47 MPa side length of 55 μm Adhesion strength of an only-circular pattern with a 40 MPa diameter of 40 μm Adhesion strength of a combination-shaped pattern of 52 MPa squares with a side length of 55 μm and circles with a diameter of 40 μm

In the method provided in the present disclosure, the adhesion strength of the sprayed coating is changed by changing a combination manner of the textured patterns. For the textured patterns in three combination manners including an only square shape, an only circle shape and a shape of alternating the squares and the circles, the respective adhesion strengths of the sprayed coating are different. As compared with the existing texturing method for improving strength of the coating, the parameter of the textured patterns is optimized. In the present disclosure, a laser texturing method is used for controlling a parameter of the laser process, to obtain textured geometrical patterns with dimensions arranged regularly at a density on the surface of the substrate. As a processing before spraying, the textured patterns formed by alternately combining the squares and the circles are prearranged on a surface of a material. As compared with the only-square textured pattern and the only-circular textured pattern, a problem in the single-shaped patterns that stress is centralized in a certain direction and positions of adhesion weak points are uniform can be solved with the combination-shaped pattern. That is, in the only-square textured patterns, weak points of the squares are located at the same or similar positions of the squares, which results in easily cracking of the whole coating in a certain direction. In the combination-shaped patterns, a weak point of the square textured pattern and a weak point of the circular textured pattern are located at different positions of the respective patterns. Therefore, the square textured pattern and the circular textured pattern can complement with each other in a case that the square textured pattern and the circular textured pattern are combined together, thereby improving the overall adhesion strength. A mechanism in which the strength of the sprayed coating is improved by combining the square pattern and the circular textured pattern is researched by changing a characteristic of the single type of the traditional textured pattern, and an optimal parameter of the textured patterns for effectively improving adhesion strength of the coating is further researched. Therefore, the bonding force between the coating and the substrate is improved, so that the sprayed coating can be applied into the engineering practices with a long service life.

A structure for improving adhesion strength of a coating is further provided according to the embodiment of the present disclosure, which includes a substrate, textured patterns prepared on the substrate, and a coating sprayed on the textured patterns. The textured patterns include multiple columns of square patterns and multiple columns of circular patterns. The square patterns and the circular patterns are arranged alternately. One column of circular patterns is arranged between each pair of adjacent columns of square patterns. A distance between the square and the circle adjacent to the square in the textured patterns is 60 μm. A side length of the square is at least one of 20 μm, 35 μm, 55 μm or 70 μm. A diameter of the circle is at least one of 15 μm, 25 μm, 40 μm or 60 μm. The substrate is made of stainless steel, and furthermore is made of FV520B, and the coating is a NiCrBSi ceramic coating.

Nineteenth Embodiment

A method for improving adhesion strength of a coating is provided in the present embodiment, in which, a side length of a square pattern and a width of a channel shape in textured patterns formed by alternately combining squares and channel shapes are regulated to improve adhesion strength of the coating. The method includes the following steps S192 and S193 in addition to the same steps as the above embodiments.

In step S192, textured patterns are prepared. Combination-shaped patterns formed by combining squares and channel shapes are textured on a surface of a substrate using a laser process based on bionics.

In step S193, a parameter is regulated. A spraying process parameter and a parameter of the textured patterns are regulated based on the textured patterns formed in step S192, to obtain textured patterns formed by alternately combining the squares and the channel shapes. In the textured patterns, a distance between the square and the channel shape adjacent to the square is 65 μm, a side length of the square is 20 μm, and a width of the channel shape is 15 μm. Alternatively, a distance between the square and the channel shape adjacent to the square is 65 μm, a side length of the square is 35 μm, and a width of the channel shape is 25 μm. Alternatively, a distance between the square and the channel shape adjacent to the square is 65 μm, a side length of the square is 55 μm, and a width of the channel shape is 40 μm. Alternatively, a distance between the square and the channel shape adjacent to the square is 65 μm, a side length of the square is 70 μm, and a width of the channel shape is 60 μm.

For the textured patterns with the shape parameters, a laser powers is 14 W, a scanning speed is 800 mm/s, and the number of processing is 2. The textured patterns are textured by: texturing at least three columns of channel-shaped patterns, where a preset distance is reserved between each pair of adjacent columns of channel-shaped patterns, and the preset distance is greater than a side length of the square to be textured; and texturing one column of square patterns between each pair of adjacent columns of channel-shaped patterns.

Comparative Example

The tensile test is performed on the combination-shaped textured patterns formed by alternately combining the channel shapes and the squares with different dimensions prepared in the above embodiment, and on an only-channel-shaped pattern and an only-square pattern after a coating is sprayed on the respective textured patterns. The adhesion strength is indicated by a ratio of a force under which the coating fractures from the substrate to the area of the coating.

The testing results are as shown in FIG. 29 and FIG. 30. FIG. 29 is a curve diagram showing comparison of adhesion strength for the combination-shaped textured pattern, the only-channel-shaped pattern and the only-square pattern. FIG. 30 shows adhesion strength between the coating and the substrate for the combination-shaped textured patterns with different dimensions formed by alternately combining the channel shapes and the circles. Comparison of adhesion strength for the combination-shaped textured patterns with different dimensions is as shown in the following Table.

TABLE 15 Comparison of Adhesion strength for Combination-shaped Textured Patterns with Different Dimensions Side length of a square 20 μm 35 μm 55 μm 70 μm Width of a channel shape 15 μm 25 μm 40 μm 60 μm Adhesion strength 26 MPa 32 MPa 48 MPa 56 MPa

In a case that the textured patterns are formed by alternately combining the channel shapes and the squares, the adhesion strength is affected by both the side length of the square and the width of the channel shape. Taking the above Table as an example, the adhesion strength is at a minimum value 26 MPa in a case that the side length of the square is 20 μm and the width of the channel shape is 15 μm. The adhesion strength is at a maximum value 56 MPa in a case that the side length of the square is 70 μm and the width of the channel shape is 60 μm. The adhesion strength is 32 MPa in a case that the side length of the square is 35 μm and the width of the channel shape is 25 μm. The adhesion strength is 48 MPa in a case that the side length of the square is 55 μm and the width of the channel shape is 40 μm. It can be seen that the adhesion strength increases with an increase in the side length of the square and an increase in the width of the channel shape in a case that the side length of the square ranges from 20 μm to 70 μm and the width of the channel shape ranges from 15 μm to 60 μm.

As compared with the single-shaped textured pattern, the alternate-combination-shaped textured pattern has higher adhesion strength. Comparison of adhesion strength for the only-square textured pattern, the only-channel-shaped textured pattern and the combination-shaped textured pattern formed by alternately combining the channel shapes with the same dimension as the only-channel-shaped textured pattern and the squares with the same dimension as the only-square textured pattern is as shown in the following Table.

TABLE 16 Comparison of Adhesion strength for Single-Shaped Pattern and Combination-shaped Pattern with the same Dimension Adhesion strength of an only-square pattern with a side 47 MPa length of 55 μm Adhesion strength of an only-channel-shaped pattern with 36 MPa a width of 40 μm Adhesion strength of a combination-shaped pattern of squares 48 MPa with a side length of 55 μm and channel shapes with a width of 40 μm

In the method provided in the present disclosure, the adhesion strength of the sprayed coating is changed by changing a combination manner of the textured patterns. For the textured patterns in an only square shape, an only channel shape or a shape of alternating the squares and the channel shapes, the respective adhesion strength of the sprayed coating are different. As compared with the existing texturing method for improving strength of the coating, the parameter of the textured patterns is optimized. In the present disclosure, a laser texturing method is used for controlling a parameter of the laser process, to obtain textured geometrical patterns with dimensions and arranged regularly at a density on the surface of the substrate. As a processing before spraying, the textured patterns formed by alternately combining the squares and the channel shapes are prearranged on a surface of a material. As compared with the only-square textured pattern and the only-channel-shaped textured pattern, a problem in the single-shaped patterns that stress is centralized in a certain direction and positions of adhesion weak points are uniform can be solved with the combination-shaped patterns. That is, in the only-square textured patterns, the weak points in the squares are located at the same or similar positions of the squares, which results in easily cracking of the whole coating in a certain direction. In the combination-shaped patterns, a weak point in the square textured pattern and a weak point of the channel-shaped textured pattern are located at different positions of the respective textured patterns. Therefore, the square textured pattern and the channel-shaped textured pattern can complement with each other in a case that the square textured pattern and the channel-shaped textured pattern are combined together, thereby improving the overall adhesion strength. A mechanism in which the strength of the sprayed coating is improved by combining the square textured pattern and the channel-shaped textured pattern is researched by changing a characteristic of the single type of the traditional textured pattern, and an optimal parameter of the textured patterns for effectively improving adhesion strength of the coating is further researched. Therefore, the bonding force between the coating and the substrate is improved, so that the sprayed coating can be applied into the engineering practices with a long service life.

A structure for improving adhesion strength of a coating is further provided according to the embodiment of the present disclosure, which includes a substrate, textured patterns prepared on the substrate, and a coating sprayed on the textured patterns. The textured patterns include multiple columns of square patterns and multiple columns of channel-shaped patterns. The square pattern and the channel-shaped pattern are arranged alternately. One column of channel-shaped patterns is arranged between each pair of adjacent columns of square patterns. A distance between the square and the channel shape adjacent to the square in the textured patterns is 65 μm. A side length of the square is at least one of 20 μm, 35 μm, 55 μm or 70 μm. A width of the channel shape is at least one of 15 μm, 25 μm, 40 μm or 60 μm. The substrate is made of stainless steel, and furthermore is made of FV520B, and the coating is a NiCrBSi ceramic coating.

Twentieth Embodiment

A method for improving adhesion strength of a coating is provided in the present embodiment, in which, a side length of a regular hexagon and a width of a channel shape in textured patterns formed by alternately combining regular hexagons and channel shapes are regulated to improve the adhesion strength of the coating. The method includes the following steps S202 and S203 in addition to the same steps as the above embodiments.

In step S202, textured patterns are prepared. Combination-shaped patterns formed by combining regular hexagons and channel shapes are textured on a surface of a substrate using a laser process based on bionics.

In step S203, a parameter is regulated. A spraying process parameter and a parameter of the textured patterns are regulated based on the textured patterns formed in step S202, to obtain textured patterns formed by alternately combining the regular hexagons and the channel shapes. In the textured patterns, a distance between the regular hexagon and the channel shape adjacent to the regular hexagon is 60 μm, a side length of the regular hexagon is 20 μm, and a width of the channel shape is 15 μm. Alternatively, a distance between the regular hexagon and the channel shape adjacent to the regular hexagon is 60 μm, a side length of the regular hexagon is 30 μm, and a width of the channel shape is 25 μm. Alternatively, a distance between the regular hexagon and the channel shape adjacent to the regular hexagon is 60 μm, a side length of the regular hexagon is 45 μm, and a width of the channel shape is 40 μm. Alternatively, a distance between the regular hexagon and the channel shape adjacent to the regular hexagon is 60 μm, a side length of the regular hexagon is 60 μm, and a width of the channel shape is 60 μm.

For all of the textured patterns with the shape parameters, a laser power is 14 W, a scanning speed is 800 mm/s, and the number of processing is 2. The textured patterns are textured by: texturing at least three columns of channel-shaped patterns, where a preset distance is reserved between each pair of adjacent columns of channel-shaped patterns, and the preset distance is greater than a length of the longest diagonal line of the regular hexagon to be textured; and texturing one column of regular-hexagonal patterns between each pair of adjacent columns of channel-shaped patterns.

Comparative Example

The tensile test is performed on the combination-shaped textured patterns formed by alternately combining the channel shapes and the regular hexagons with different dimensions prepared in the above embodiment, and on an only-channel-shaped pattern and an only-regular-hexagonal pattern after a coating is sprayed on the respective pattern. The adhesion strength is indicated by a ratio of a force under which the coating fractures from the substrate to the area of the coating.

The testing results are as shown in FIG. 31 and FIG. 32. FIG. 31 is a curve diagram showing comparison of adhesion strength for the combination-shaped textured pattern, the only-channel-shaped pattern and the only-regular-hexagonal pattern. FIG. 32 shows adhesion strength between the coating and the substrate for the combination-shaped textured patterns with different dimensions formed by alternately combining the channel shapes and the regular hexagons. Comparison of adhesion strength for the combination-shaped textured patterns with different dimensions is as shown in the following Table.

TABLE 17 Comparison of Adhesion strength for Combination-shaped Textured Patterns with Different Dimensions Side length of a regular hexagon 20 μm 30 μm 45 μm 60 μm Width of a channel shape 15 μm 25 μm 40 μm 60 μm Adhesion strength 36 MPa 42 MPa 53 MPa 62 MPa

In a case that the textured patterns are formed by alternately combining the channel shapes and the regular hexagons, the adhesion strength is affected by both the side length of the regular hexagon and the width of the channel shape. Taking the above Table as an example, the adhesion strength is at a minimum value 36 MPa in a case that the side length of the regular hexagon is 20 μm and the width of the channel shape is 15 μm. The adhesion strength is at a maximum value 62 MPa in a case that the side length of the regular hexagon is 60 μm and the width of the channel shape is 60 μm. The adhesion strength is 42 MPa in a case that the side length of the regular hexagon is 30 μm and the width of the channel shape is 25 μm. The adhesion strength is 53 MPa in a case that the side length of the regular hexagon is 45 μm and the width of the channel shape is 40 μm. It can be seen that the adhesion strength increases with an increase in the side length of the regular hexagon and an increase in the width of the channel shape in a case that the side length of the regular hexagon ranges from 20 μm to 60 μm and the width of the channel shape ranges from 15 μm to 60 μm.

As compared with the single-shaped textured pattern, the alternate-combination-shaped textured pattern has higher adhesion strength. Comparison of adhesion strength for the only-regular-hexagonal textured pattern, the only-channel-shaped textured pattern and the combination-shaped textured pattern formed by alternately combing the channel shapes with the same dimension as the only-channel-shaped textured pattern and the regular hexagons with the same dimension as the only-regular-hexagonal textured pattern is as shown in the following Table.

TABLE 18 Comparison of Adhesion strength for Single-Shaped Pattern and Combination-shaped Pattern with the same Dimension Adhesion strength of an only-regular-hexagonal pattern with 48 MPa a side length of 45 μm Adhesion strength of an only-channel-shaped pattern with 36 MPa a width of 40 μm Adhesion strength of a combination-shaped pattern of regular 53 MPa hexagons with a side length of 45 μm and channel shapes with a width of 40 μm

In the method provided in the present disclosure, the adhesion strength of the sprayed coating is changed by changing a combination manner of the textured patterns. For the textured patterns in an only regular hexagon shape, an only channel shape and a shape of alternately combining the regular hexagons and the channel shapes, the respective adhesion strength of the sprayed coating are different. As compared with the existing texturing method for improving strength of the coating, the parameter of the textured patterns is optimized. In the present disclosure, a laser texturing method is used for controlling a parameter of the laser process, to obtain textured geometrical patterns with dimensions arranged regularly at a density on the surface of the substrate. As a processing before spraying, the textured patterns formed by alternately combining the regular hexagons and the channel shapes are prearranged on a surface of a material. As compared with the only-regular-hexagonal textured pattern and the only-channel-shaped textured pattern, a problem in the single-shaped patterns that stress is centralized in a certain direction and positions of adhesion weak points are uniform can be solved with the combination-shaped pattern. That is, in the only-regular-hexagonal textured patterns, weak points of the regular hexagons are located at the same or similar positions of the regular hexagons, which results in easily cracking of the whole coating in a certain direction. In the combination-shaped patterns, a weak point of the regular-hexagonal textured pattern and a weak point of the channel-shaped textured pattern are located at different positions of the respective textured patterns. Therefore, the regular-hexagonal textured pattern and the channel-shaped textured pattern can complement with each other in a case that the regular-hexagonal textured pattern and the channel-shaped textured pattern are combined together, thereby improving the overall adhesion strength. A mechanism in which the strength of the sprayed coating is improved by combining the regular-hexagonal textured pattern and the channel-shaped textured pattern is researched by changing a characteristic of the single type of the traditional textured pattern, and an optimal parameter of the textured patterns for effectively improving adhesion strength of the coating is further researched. Therefore, the bonding force between the coating and the substrate is improved, so that the sprayed coating can be applied into the engineering practices with a long service life.

A structure for improving adhesion strength of a coating is further provided according to the embodiment of the present disclosure, which includes a substrate, textured patterns prepared on the substrate, and a coating sprayed on the textured patterns. The textured patterns include multiple columns of regular-hexagonal patterns and multiple columns of channel-shaped patterns. The regular-hexagonal pattern and the channel-shaped pattern are arranged alternately. One column of channel-shaped patterns is arranged between each pair of adjacent columns of regular-hexagonal patterns. A distance between the regular hexagon and the channel shape adjacent to the regular hexagon in the textured patterns is 65 μm. A side length of the regular hexagon is at least one of 20 μm, 30 μm, 45 μm or 60 μm. A width of the channel shape is at least one of 15 μm, 25 μm, 40 μm or 60 μm. The substrate is made of stainless steel, and furthermore is made of FV520B, and the coating is a NiCrBSi ceramic coating.

With the method in the present disclosure, the adhesion strength of the sprayed coating is changed by changing the side length of the square textured pattern, and the adhesion strength of the sprayed coating changes with the side length of the square textured pattern. As compared with the existing texturing method for improving strength of the coating, a parameter of the textured patterns is optimized. In the present disclosure, a laser texturing method is used for controlling a parameter of the laser process, to obtain textured geometrical patterns with dimensions arranged regularly at a density on the surface of the substrate. As a processing before spraying, square textured patterns with different side lengths are prearranged on a surface of a material. A mechanism for improving adhesion strength of the sprayed coating for different side lengths is researched by changing the side length of the square textured pattern, and an optimal side length of the textured pattern for effectively improving adhesion strength of the coating is further researched. Therefore, bonding force between the coating and the substrate is improved, so that the sprayed coating can be applied into the engineering practices with a long service life.

In the above embodiments, the substrate is made of stainless steel, and furthermore is made of FV520B, a processing depth of the obtained textured patterns is 60 μm, and the selected coating is a NiCrBSi ceramic coating. A sprayed coating with a depth of 500 μm is obtained by supersonic plasma spraying. A particle size of NiCrBSi powder ranges from 50 μm to 60 μm. The laser used here is a pulse laser. The depth of the textured pattern is depended on the energy of the laser and the number of processing. Textured patterns in a shape with a dimension and a distance may be drawn in advance using system-provided drawing software, and a surface of a specimen is processed, to obtain textured patterns in a structure with an accurate dimension.

The foregoing is only preferred embodiments of the present disclosure, it should be noted that multiple improvements and modifications can also be made by those skilled in the art without departing from the technical principle of the present disclosure, and the improvement and the modification are regarded to fall within the protection scope of the present disclosure.

The embodiments of the present disclosure are described in a progressive way, and each embodiment lays emphasis on differences from other embodiments. For the same or similar parts between various embodiments, one may refer to the description of other embodiments.

According to the above description of the disclosed embodiments, those skilled in the art can implement or practice the present disclosure. Many modifications to these embodiments are apparent for those skilled in the art, and general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present disclosure. Hence, the present disclosure is not limited to the embodiments disclosed herein, but is to conform to the widest scope in accordance with the principles and novel features disclosed herein. 

1. A method for improving adhesion strength of a coating, comprising: step 1), preparing textured patterns, wherein at least one type of patterns are textured on a surface of a substrate using a laser process based on bionics; step 2), regulating a parameter, wherein a spraying process parameter is regulated based on a parameter of the textured patterns formed in step 1); and step 3), spraying a coating, wherein spraying is performed on the substrate obtained in step 1) using a supersonic plasma spraying method.
 2. The method for improving the adhesion strength of the coating according to claim 1, wherein the parameter of the textured patterns comprises one or more of a pattern shape, a pattern distance, a pattern dimension and pattern arrangement.
 3. The method for improving the adhesion strength of the coating according to claim 2, wherein the pattern shape comprises one of a channel shape, a square, a regular hexagon and a circle, or a combination thereof.
 4. The method for improving the adhesion strength of the coating according to claim 2, wherein the pattern dimension comprises one of a depth, a side length, a width and a diameter, or a combination thereof.
 5. The method for improving the adhesion strength of the coating according to claim 3, wherein the pattern shape comprises the channel shape and the circle, the channel shape and the circle are combined alternately, and the step 1) comprises: texturing at least three columns of circular patterns, wherein a preset distance is reserved between each pair of adjacent columns of circular patterns, the preset distance is greater than a width of a channel-shaped pattern to be textured, and texturing a column of channel-shaped patterns between each pair of adjacent columns of circular patterns.
 6. The method for improving the adhesion strength of the coating according to claim 3, wherein the pattern shape comprises the regular hexagon and the square, the regular hexagon and the square are combined alternately, and the step 1) comprises: texturing at least three columns of square patterns, wherein a preset distance is reserved between each pair of adjacent columns of square patterns, the preset distance is greater than a length of the longest diagonal line of a regular-hexagonal pattern to be textured; and texturing a column of regular-hexagonal patterns between each pair of adjacent columns of square patterns.
 7. The method for improving the adhesion strength of the coating according to claim 3, wherein the pattern shape comprises the regular hexagon and the circle, the regular hexagon and the circle are combined alternately, and the step 1) comprises: texturing at least three columns of circular patterns, wherein a preset distance is reserved between each pair of adjacent columns of circular patterns, the preset distance is greater than a length of the longest diagonal line of a regular-hexagonal pattern to be textured; and texturing a column of regular-hexagonal patterns between each pair of adjacent columns of circular patterns.
 8. The method for improving the adhesion strength of the coating according to claim 3, wherein the pattern shape comprises the square and the circle, the square and the circle are combined alternately, and the step 1) comprises: texturing at least three columns of circular patterns, wherein a preset distance is reserved between each pair of adjacent columns of circular patterns, the preset distance is greater than a side length of a square pattern to be textured; and texturing a column of square patterns between each pair of adjacent columns of circular patterns.
 9. The method for improving the adhesion strength of the coating according to claim 3, wherein the pattern shape comprises the square and the channel shape, and the square and the channel shape are combined alternately, and the step 1) comprises: texturing at least three columns of channel-shaped patterns, wherein a preset distance is reserved between each pair of adjacent columns of channel-shaped patterns, the preset distance is greater than a side length of a square pattern to be textured; and texturing a column of square patterns between each pair of adjacent columns of channel-shaped patterns.
 10. The method for improving the adhesion strength of the coating according to claim 3, wherein the pattern shape comprises the regular hexagon and the channel shape, the regular hexagon and the channel shape are combined alternately, and the step 1) comprises: texturing at least three columns of channel-shaped patterns, wherein a preset distance is reserved between each pair of adjacent columns of channel-shaped patterns, the preset distance is greater than a length of the longest diagonal line of a regular-hexagonal pattern to be textured; and texturing a column of regular-hexagonal patterns between each pair of adjacent columns of channel-shaped patterns.
 11. The method for improving the adhesion strength of the coating according to claim 1, before step 1), further comprising a substrate preprocessing step of polishing and cleaning the surface of the substrate.
 12. The method for improving the adhesion strength of the coating according to claim 1, wherein in step 1), the substrate is made of stainless steel.
 13. The method for improving the adhesion strength of the coating according to claim 1, wherein the coating in step 3) is a NiCrBSi ceramic coating, the sprayed coating obtained by the supersonic plasma spraying method has a thickness of approximately 500 μm, and a particle size of used NiCrBSi powder ranges from 50 μm to 60 μm.
 14. The method for improving the adhesion strength of the coating according to claim 4, wherein the textured patterns prepared in step 1) have a depth ranging from 30 μm to 120 μm, and a diameter ranging from 35 μm to 65 μm.
 15. A structure for improving adhesion strength of a coating, comprising: a substrate; textured patterns having at least one type of pattern prepared on the substrate; and a coating sprayed on the textured patterns.
 16. The structure according to claim 15, wherein the textured pattern is in a shape of one of a square, a channel shape, a circle and a regular hexagon, or a combination thereof.
 17. The structure according to claim 15, wherein the substrate is made of stainless steel, and the coating is a NiCrBSi ceramic coating. 